Repeated kernel panics on Mac mini 2018, macOS Sonoma (14.3.1)

Most likely you have a hardware issue with the Logic Board of this Mac Mini since you don't have any of the usual third party apps known to interfere with the normal operation of macOS.

Most concerning to me are the "ProxiedDevice-Bridge" panics which is associated with the T2 security chip which controls most aspects of the system. Unfortunately the other Kernel Panic log summaries do not include any useful details.

Try disconnecting all external devices in case one of them is causing a problem.

Run Disk Utility First Aid on the hidden Container. Within Disk Utility you may need to click "View" and select "Show All Devices" before the hidden Container appears on the left pane of Disk Utility. Even if First Aid says everything is "Ok", click "Show Details" and scroll back through the report to see if any unfixed errors are listed. If so, try running First Aid again to see if the errors are fixed. If not, then you will need to run First Aid while booted into Recovery Mode, otherwise you will need to erase the whole physical SSD (Intel Macs only) followed by reinstalling macOS & restoring from a backup.

You can try a DFU firmware Revive which will reset the T2 security chip & system firmware to see if that makes any difference.

Try running the Apple Diagnostics to see if any hardware issues are detected. Unfortunately the diagnostics rarely detect issues, but if an error is reported then at least you have confirmed my suspicions.

You should make sure you have a good backup while you still can since it is very difficult to impossible to recover any data from the SSD of these newer Macs.

Unfortunately it may be hard to convince Apple to repair the computer since they do not train their techs to interpret Kernel Panic logs and don't even reference those "ProxiedDevice-Bridge" panics. The best way to get Apple to take those crashes seriously is by performing a clean install of macOS and showing the Kernel Panics still occur. It is important not to install any third party software and not to restore from a backup since Apple needs to see a factory fresh OS fail to work properly. The only other option is to contact Apple support and get Apple to escalate your case to an engineer who is able to actually examine & interpret those Kernel Panic logs & "ProxiedDevice-Bridge" logs to confirm a hardware failure.

The question then becomes does it make sense to even repair this Mac Mini? I have seen a much higher rate of Logic Board failures with the 2018-2020 Intel Macs than I have with any of the older models mostly because of the T2 security chip and having all the formerly removable components now integrated onto the Logic Board.

dannlylonglegs wrote:

Thanks again for sharing all this info! I've just run MemTest86 and it got to ~350 errors before I stopped the test - it looks like anything more than 0 is bad news? Interesting that the Mac diagnostics didn't pick up on this. Output of the MemTest86 run attached.

The Apple Diagnostics' memory test is just meant to be a quick basic test. While they do utilize similar tests, they may be performed slightly differently and may not scan all the memory in order to be completed more quickly. The Memtest86 report shows the errors occurred in a small 32MB section of upper memory (around the 6.5/6.8GB section).

Will the bad RAM be the cause of all the kernel panics? I remember seeing someone say that OS updates can cause kernel panics if the OS starts using different (broken) parts of the RAM more often. My issues started with the Sonoma update.

Possibly.

I am thinking a 16GB RAM upgrade from a reputable brand like Crucial (installed by a proper technician) will be the next move. Any thoughts on this - is 16GB RAM for my i3 Mac overkill? I don't run out of RAM at the moment but I'm guessing the marginal costs of getting 8GB vs 16GB are pretty minor.

Depends on the price. You can use the memory information tab in Activity Monitor to see if you may be running close to the edge on memory. Use the computer especially with your heavier workloads for a few days. Check the memory pressure graph as a guide. If it goes red, you need more memory for those tasks. If it is yellow, you are borderline on memory. If it is green, you may be Ok on memory, but check the amount of Swap and Compressed memory listed....if it is shown in GBs, then you may not have enough memory for the workload.

I've seen the stuff about not mixing RAM brands etc.

It is generally a good idea to use identical paired memory. Some computers & memory are more lenient than others. You just never know for sure. I have installed mixed memory into Apple systems for years, but never in a 2018 Mini. I've mixed different Apple modules using different memory chips, and mixed Apple memory with Crucial and OWC. My organization did this mostly with the MBPro 2012 models where we installed one large module paired with one of Apple's original modules since we needed to save money (4GB to 10GB with a single module).

Btw I haven't got any kernel panic reports in that folder?

Check the "Retired" subfolder. macOS is sometimes aggressive in moving logs there.

Continued....

As I said, I reinstalled the OS today (Internet Recovery, not a full system reset) so will see if that improves anything. If there were issues with something in the OS install that remained after fixing the dodgy external drive I am hoping that this should have been enough to clear them out. Would appreciate if you've got any other pointers on deep clean type stuff I should be doing or broader thoughts on how I'm approaching this.

You can try creating and running a bootable Memtest86 USB stick to perform a longer more thorough memory test than the Apple Diagnostics. Maybe it will throw an error to help you identify a hardware issue with the Logic Board. Just run Memtest86 with default settings on the 2018 - 2020 Intel Macs since I've had some issues when running with modified Memtest86 settings on them....not sure if they are legit problems or just a compatibility issue (I know the Memtest86 developers have to modify the configuration just to get the utility to boot on the 2018-2020 Intel Macs which is why I'm not certain it is safe to deviate from default settings).

Just out of curiosity, post about three of the Kernel Panic logs here by using the "Additional Text" icon which looks like a piece of paper on the forum editing toolbar. Those logs can be found in "/Library/Logs/DiagnosticReports" and will have file names beginning with "kernel" and usually ending in ".panic".

Otherwise, I have nothing else to add. From everything I've personally experienced while supporting my organization's Macs and reading this forum for years, everything tells me this will be a bad Logic Board. I only mentioned the other things just on the slim chance they could possibly be causing a problem.

dannlylonglegs wrote:

What did you mean with "Run Disk Utility First Aid on the hidden Container"? I have Show All devices enabled in Disk Utility but can't tell what's hidden and what isn't.

If you compare the left pane of Disk Utility before & after (or between "Show All Devices" & "Show Only Volumes" you will see the Container appear & disappear as well as the physical drives. Disk Utility defaults to a volume only view which is very limiting.

Interestingly I didn't have any kernel panics at all yesterday. When I do get kernel panics, it's usually when I wake my computer back up (eg this morning it crashed about 2 mins after I woke it up, it has been stable since).

I find that with the 2016 & 2017 models this usually indicates an SSD failure. Some of the crash logs in the EtreCheck report kind of indicate an SSD or file system issue, but it may just be the T2 security chip since there are "ProxiedDevice-Bridge" panics.....the T2 security chip handles access to the SSD.

When you say about potential issues with external devices, what kinds of things do you mean? I'm using the USB hub in my monitor connected with a few things connected (lights, iPad for Sidecar, Logitech receiver) and then I've got my external SATA enclosure connected. These have always been connected, broad question of course but what kind of thing might lead to these devices causing kernel panics?

The USB-C ports are tied to the PCIe bus which is tied to the CPU making an external device, especially a Thunderbolt based devices more likely to cause a panic. Displays as well. A couple years ago I had an external drive with a file system that had issues, those issues would cause the Mac to Kernel Panic whenever the external drive was connected & trying to scan & mount the corrupted volume.

When trying to troubleshoot a problem, it is always best to disconnect everything you can in order to have as minimal configuration as possible since you minimize the things which can be potentially causing a problem. That is also why testing in Safe Mode or with a clean install (no third party apps & no restoration from a backup) is so important in determining if an issue is caused by hardware or software. This is especially important when trying to present a case to Apple to repair a Mac when the diagnostics report no issues.

Are there any diagnostic tools I can feed the error logs into to get an idea of any commonalities or is this best left to dedicated Apple support engineers?

Unfortunately the macOS logs are worthless for troubleshooting these days. The Kernel Panic logs are about the only logs that can provide some useful information on the possible cause.

I'm 95% sure that the Logic Board on this Mac is bad, but it is always best to try to confirm especially when you also need to convince Apple.

dannlylonglegs wrote:

Could the dodgy external drive/force reboots have damaged that initial clean OS reinstall I did to the point my Mac would keep getting kernel panics?

Doubtful since macOS system files now reside on a read-only signed & sealed system volume. macOS won't boot if something happens to a system file. I'm not sure about any third party software which installs drivers, whether they have any protections.

Would it make any sense if I was still getting kernel panics even after I'd disconnected the bad external drive? 

Then you have something else causing them besides the external drive issues.

Given how badly the corrupted external drive was previously crashing things I definitely know that the external drive is fixed now (it works fine in Disk Utility, Time Machine etc). But I don't know if the kernel panics are also related to the formerly-corrupt external drive

A severely corrupted file system can cause Kernel Panics when the drive is connected...I have personally seen that happen although it is very rare. One thing you have not considered is that the Logic Board is bad and corrupted the external drive.

I don't specifically know what the OS reinstall today would have actually fixed to stop the kernel panics occurring, do you have any thoughts on this?

I doubt it fixed anything.

Some broader questions like in terms of working out where to go next if the issues continue:

1. Do you have any thoughts on procedures etc for tracking these kernel panics (if they continue) where they are difficult to reproduce?

When trying to troubleshoot an intermittent issue, you need to notice patterns. What you are doing at the time, what devices are connected, what app is being used, etc. In the case of Kernel Panics, you can try to look at the Kernel Panic log for possible clues. If the Kernel Panics are not the same, it usually indicates a memory failure.

2. If it is an SSD failure, is it likely to get worse? Obviously very broad question but I don't know how these SoC SSDs fail

Most SSD failures I have seen have involved the SSD's controller not communicating properly with the system. Usually the failure will progress fairly quickly to a complete failure. These types of SSD failures never show up in the SSD's health attributes since it is the SSD controller which has the problem. I have rarely seen an SSD fail due to over use or other issues which can be monitored through the SSD's health attributes although Apple's SSDs have very little health information available these days.

3. Say I eventually present it as absolutely having issues to Apple (complete reset and still getting kernel panics). My AppleCare has long expired on this one (I did actually have it for 3 years initially) so I am assuming they will charge for whatever work I can convince them needs doing. I don't want to throw away the Mac away if it's "working" but given its relative age I imagine major repairs (logic board etc) are probably uneconomical at this point. Do you have any info on what Apple would charge/actually be able to repair? From what you've said I'm guessing it would be a logic board replacement which sounds like £££.

I don't recall what a Logic Board repair will cost for a 2018 Mac Mini, although it is expensive. My organization had to have a Logic Board replaced for a 2018 Mini about a year ago. We were definitely questioning whether it was worth repairing it. For reference, that is the first Mac Mini Logic Board our organization has ever had to replace....this is going back decades to the old PPC Minis. I have no faith in the 2018 - 2020 Intel Macs' Logic Boards (Mini, iMac, or laptop) since I know they have a much higher rate of failure due to the T2 chip.

I’m not proficient enough to read those logs by any means, but I had the same problem with my Mac mini 2018 after installing Sonoma. I did most of the things you did, but was able to finally fix the kernel panics with a different monitor cable - hdmi to usbc. I also turned on “Prevent automatic sleeping when the display is off” under Energy Saver (the rest of the settings under Energy Saver are off) and manually turned off DDC/CI from the monitor menu.

Restart in Safe Mode. This will perform a Disk Repair, clear cache files and only load Apple Software, extensions and fonts. The boot up will be slow and can take some time - Normal.

Safe Mode will also eliminate Third Party Software, extensions and drivers from loading. It will only load the Minimum amount of Core Apple Processes to allow the the computer to function at a reduced Level of Performance 

Does the issue present in this mode ?

Kernel panics - This system has experienced kernel panics. This could be a sign of hardware failure.

Not definitive but an indicator of a serious and possible issue

HP Z27n 2560 x 1440

Kernel Extensions:

/Library/Application Support/Logitech.localized/Logitech Options.localized

2024-03-06 10:56:42 Kernel Panic (10 times)

First occurrence: 2024-03-01 10:01:04

Details:

panic(cpu 0 caller 0xfffffff0206c6f60): macOS panic detected

Panicked task 0xffffffde19fe5190: 0 pages, 169 threads: pid 0: kernel_

task

Everything looks about right except for

disk2 - SanDisk Ultra 61.53 GB

External USB 5 Gbit/s USB

disk2s1 - N*****E (MS-DOS FAT32) 273 MB

disk2s2 134 MB

disk2s3 - C*********************9 (MS-DOS FAT12) 61.12 GB (11.16 GB used)