VLC freezes when playing local MP4 videos on iMac

Question

VLC freezes when playing local MP4 videos on iMac

I have digital copies of films on my external hard drive (films I own that I ripped into mp4 just for my own use, not downloads or torrents etc). I try to watch them through VLC on my imac (M4, 24GB, 2024) and it constantly freezes after a few minutes when watching. Even a half-hour tv show freezes after a few minutes.

Films also freeze if I move the file onto the desktop of the imac, so

it's not the external hard drive issue. Might be 3 minutes, might be 7

but it still freezes at least 6-10 times every time I run a 45 minute tv

show.

I know it's not the external hard drive, I know it's not the Mp4s because I can play this on my macbook air (M4, 2025) for entire films with no issues whatsoever. I haven't had it skip once for 2 hour films on the macbook air, but it's constant on the imac.

Would welcome advice on how to resolve this-- or at least suggestions on what to look at in order to track down why this is freezing?

thank you

iMac 24″

Posted on Jan 14, 2026 1:10 PM

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Answer 1

Top-ranking reply

HWTech

Community+ 2026

Level 9

70,238 points

Jan 15, 2026 5:22 PM in response to HeatedBlanket

Try booting into Safe Mode to see if that makes any difference, unfortunately Safe Mode these days may not be as conclusive.

You should try disconnecting all external devices (except for those required to interact with the iMac) just in case one of them is causing a problem.

Regardless of how Safe Mode works out, try running the third party app EtreCheck and posting the complete report here so we can examine it for possible clues. It is best to run the iMac normally for a while & try playing an MP4 stored on the internal SSD, then afterwards run EtreCheck so it can collect some relevant performance metrics just after attempting to play an MP4.

How to use the Add Text Feature When Posting an EtreCheck Report - Apple Community

Edit: Also, you may want to install the macOS 15.7.3 update patches just in case they may resolve the problem. And make sure VLC is completely up to date.

Have you tried playing any other types of videos? And do they suffer the same fate?

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Answer 2

-g

Level 4

3,539 points

Jan 14, 2026 6:23 PM in response to HeatedBlanket

>> the problem is definitely the imac

i may suspect macOS bug, corrupted install, or player conflicts before the iMac hardware — but what are you suggesting, bad ram, bad SSD, bad GPU, bad hub or keyboard?

do the mp4 files error if you drag them into an open web browser window and play from web browser

is it possible to boot into an External Sequoia SSD to see if the problem follows — I’m guessing you are currently running Tahoe… it shouldn’t take that long to Erase a FAST SSD and install/update another macOS, and VLC player to test— and I would think there lies your answer…

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Answer 3

-g

Level 4

3,539 points

Jan 15, 2026 6:05 PM in response to HeatedBlanket

thanks for posting back, i was just wondering if you were able to get back to work

the 'trick' installing a fresh macOS to a freshly Erased SSD -- booting off it (you don't need to log in with your Apple ID) -- running Software Update to update macOS -- and installing a current version of the SUSPECT (in this case VLC player) from a fresh download off the developers -- and seeing if the problem clears -- SHOULD BE CONCLUSIVE

what it does is isolate macOS and SUSPECT on a clean system

Sequoia is up to 15.7.3 -- Sequoia is a mature macOS -- I wouldn't expect it to have VLC conflicts

(I) would put Sequoia on the empty SSD and test of the clean updated system

Tahoe is not 'terrible' it's just bleeding edge (like your M4 machine) -- they all start out rough

HWTech makes a good point about "disconnecting all external devices (except for those required to interact with the iMac) just in case one of them is causing a problem." it could be a hub, 3rd party keyboard -- and play your MP4 from the boot SSD (probably copy them to your DeskTop

the 'trick' dragging files into a web browser is also old school -- a color-managed web browser (like Safari, FireFox, Chrome) will perform similar to Photoshop and display ICC-profile tagged images through the monitor profile -- ie, a colormanaged picture viewer -- if the image is high resolution click on the detain you want to inspect at 100 percent Actual Pixels

HIGHLY recommend buying a SanDisk Extreme Go Portable SSD, 1-2TB off Amazon or Costco -- it's fast enough not to slow you down -- also one of the cheapest SSD

>> If you have any ideas on what could be causing the imac to not run videos properly, I'm happy to hear it.

since you are running Sequoia (run the .3 update) -- I would bet on system conflicts/corruption. third party external devices, non Apple keyboard, mouse, input devices

i got lost in your bullet points ... have you posted an etrecheck.com report here?

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Answer 4

Jan 15, 2026 3:34 PM in response to -g

Hi, thank you for the comment.

>> i may suspect macOS bug, corrupted install, or player conflicts before

the iMac hardware — but what are you suggesting, bad ram, bad SSD, bad

GPU, bad hub or keyboard?

Genuinely do not know, that's why I'm here. I just know it works perfectly on one computer and does not function on the other.

>>do the mp4 files error if you drag them into an open web browser window and play from web browser

Did not know I could do this, thank you. This is a decent make-do until this can be resolved. No, interestingly, it does NOT cause a problem when I move it to a web browser. It DOES continue to do it when I move the mp4 to the actual desktop of the computer. So not sure what that means.

>>is it possible to boot into an External Sequoia SSD to see if the

problem follows — I’m guessing you are currently running Tahoe… it

shouldn’t take that long to Erase a FAST SSD and install/update another

macOS, and VLC player to test— and I would think there lies your answer…

I'm actually running Sequoia 15.7.1 on both the imac and macbook air. I did delete VLC and download it again, and it also freezes on Quicktime as well. Doesn't seem to matter what videos I am watching.

Also happens when I am watching DVDs and blu-rays when I'm playing from devices through the apple dvd player. But it's interesting that when I put it into the browser it works, very strange.

I've seen so many people saying Tahoe is pretty terrible so I have avoided it.

I don't have another external SSD to transfer 5TB to delete the external hard drive, but I do have another external SSD and I moved a couple of the videos onto the other external SSD, and the same thing happened-- shutting down constantly, freezing.

Sometimes I can write things confusingly so I'll put a bullet point here if it helps to summarise this.

imac- watching mp4 videos with VLC on external hard drive A does not work
macbook air - watching mp4 videos with VLC on external hard drive A does work
imac - watching mp4 videos with VLC on computer hard drive A does not work
macbook air - watching mp4 videos with VLC on computer hard drive A does work
imac - watching mp4 videos with VLC on external hard drive B does not work
macbook air- watching mp4 videos with VLC on external hard drive B does work
imac - watching mp4 videos on Quicktime watching videos with VLC on external hard drive A does not work
macbook air - watching videos on Quicktime watching videos with VLC on external hard drive A does work
imac- dragging mp4 videos to browser does work, quality is lost
macbook air- dragging mp4 videos to browser does work, quality is lost

If you have any ideas on what could be causing the imac to not run videos properly, I'm happy to hear it.

Thank you for your time.

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Answer 5

Old Toad

Level 10

216,196 points

Jan 16, 2026 10:42 AM in response to HeatedBlanket

How much free space do you have on your iMac boot drive?

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Answer 6

Rudegar

Level 10

181,272 points

Jan 14, 2026 2:37 PM in response to HeatedBlanket

suppose if it was me then I would test them with another computer, mac or otherwise to verify that the files themselves were not a factor.

of cause I would also test the files with other players than vlc

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Answer 7

Jan 14, 2026 4:15 PM in response to Rudegar

Thank you for the reply. As I said, the files work perfectly from my external hard drive on my macbook air. The files are absolutely fine, and can be used easily.

They will not play for more than a few minutes on my imac before freezing. The problem is my imac.

I also tried it with Quicktime, but it does the same thing-- freezes. (Also I detest Quicktime, and shouldn't have to use it when VLC works perfectly on my macbook air.

The macbook air and imac are both M4s. I do not understand why it freezes constantly on the imac and runs perfectly on the macbook air.

thanks for trying to help, I appreciate it. But the problem is definitely the imac. Just trying to figure out what that might be to resolve it.

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VLC freezes when playing local MP4 videos on iMac

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