iMac late 2013 + Mavericks + USB Sennheiser - input freeze

That's because Apple just removed it. They sent me an email saying they don't allow "polls", only discussion posts about technical problems.

So it looks like we won't have an easy way of figuring out if anyone has a 2013 iMac with a functioning USB mic/headset.

If you could answer my question here about how you downgraded to ML I'd be grateful. Thanks.

Switters,

Very easy. We I got my new iMac after I did the exchange on the Apple Store both of them was with Mountain Lion. So I keep the version for 2 weeks. During that 2 weeks no issues with my USB headsets. All of them was working fine.

So I thought that I could really be my 1st iMac the problem. So I did the upgrade to Maverick! And again problem start after 5 minutes!

So I did reopen a call with Apple Support, again they told me to go back to the Apple Store that what I did ... again. The give another iMac 2013! My third one! Again the iMac was under Mountain Lion. No issues .... So I did the upgrade after a couple of weeks to Maverick and again problem start over!

At this point, I'm really sure thats an issue with all iMac 2013 and USB.

Curious if anyone has tried installing Mountain Lion on an external drive, booting from that drive, and then testing the headsets? I may try that myself—if only as a way of quickly showing the "Geniuses" at the Apple Store that it is definitely an issue with Mavericks + iMac 2013. It's also a way for me to determine if downgrading to ML will solve my problem, before I go through all the trouble.

Okay, I've now received the first report (on Macrumors.com) of someone with an iMac 2013 with a fully functional USB headset. They said they heard crackling and popping with their first iMac with Fusion drive, and returned it. The replacement iMac he got was an SSD drive, and he said he doesn't have the cracking/popping issue anymore.

As I said over there, I doubt it's a problem with the Fusion drive—unless it's specific to the Fusion drive + Mavericks—since there is no issue with these machines and Mountain Lion.

Same issues here with my recently purchased Late 2013 iMac and a Logitech USB headset. I can occasionally get some audio from the mic upon immediately connecting it but then nada. I am also experiencing the full system freezes with no option other than to hard reset by holding down the power button.

Sometimes when it freezes it is just the input from the mouse and keyboard that stops working and others it is a total system freeze. In either event a hard reset is required.

Last night it happened overnight for apparently no reason. I thought the machine had shut down since the screen was dark and totally unresponsive but pressing the power button turned the screen on to show it frozen.

I sent feedback for what good it will do. I am really missing the Late 2009 iMac I already sold. It had none of these issues running Mavericks.

Seems like the only option here is to downgrade to Mountain Lion. I like Mavericks, but frankly I've been somewhat underwhelmed by the last two OS X releases and I'd much rather have a functional USB headset than the few features I use in Mavericks that aren't in ML.

That said, we shouldn't be forced to sacrifice one over the other.

That's encouraging. Interesting that the Apple supervisor I spoke with had never heard of this and didn't acknowledge that it's a problem, but I'm glad someone at Apple has.

I wonder if there's any point in me taking my iMac to the Apple Store on Thursday? I was thinking it would be a good idea just to make sure this problem is on the record, but I already have a case number and have spoken with a supervisor, and I don't want to waste my time if a new iMac won't help.

In this thread there is speculation that the problem is related to the Fusion Drive (though others in the thread have the issue and they don't have a Fusion Drive, so it doesn't seem certain).

Curious how many people in this thread experiencing the problem have a Fusion Drive? I do—3 TB.

Yes. 3 TB Fusion Drive

I also have a 1TB Fusion drive in my Late 2013 iMac.

Since the trend seems to be that Fusion drive users are having the issue, can anyone report that they are having these issues without Fusion drive?

Yep, 1TB Fusion drive here as well.

I did a search for "2013 iMac USB audio interface" and found several other threads with 40+ pages of responses about a similar problem. The biggest and most relevant threads are here and here.

It appears that there are two separate, but related, issues: people that are unable to use audio interfaces connected via USB, and people unable to use headsets/mics connected via USB.

With some exceptions, both of these issues seem to affect people with the 2013 iMac and Fusion Drive. According to one contributor:

Any USB2 device plugged into a USB3 port can possiblly have issues under Mavericks and formerly under ML.. though many of those issues under ML were fixed by the Devs of the USB2 devices only to 'break' again under Mav.. so yes, to fix the USB2/3 issue with USB2 devices, rolling back to ML can sometimes fix them.... depending on the device and if it was 'fixed' to work or worked okay under ML in the first place...

It seems that downgrading to ML will work if your USB headset/mic worked with ML. But many people with audio interfaces (and some with USB mics/headsets) in that other thread have pointed out that they have the same problem with ML, so it's not a sure fix.

When I first got my iMac, it had ML installed on it. Unfortunately I upgraded to Mavericks immediately and didn't have a chance to test my USB audio devices on it. However, my devices all work perfectly on my Macbook Air (which, of course, has an SSD).

1 TB Fusion Drive Logitec Headphones that worked on iMac with Marvicks the late 2013 27" iMac replaced