USB audio problems with 2013 iMac

[Fishrrman]

Thanks to aswink for the informative post, which confirms my suspicions as noted in my posts 15 and 17 above.

To "badlydrawnboy", the OP:
Again, my advice is:

If you want the problems you have to end, UN-fuse the fusion drive into separate SSD and HDD. It's not really that difficult to do.

If you're unwilling to do this, you will have to live with the problem until Apple acknowledges it and provides a fix.

There is also the possibility that it _cannot_ be "fixed" due to how fusion works (at the "block level" rather than the "file level", if my understanding is correct). This is unknown and remains to be determined.

Aside: I seem to recall from other posts on this board (where a user was trying to use the command line to create a fusion drive "manually") that something (exactly what is unknown) "changed" regarding fusion, from OS 10.8 to OS 10.9. Apple made some low-level tweak or adjustment to how fusion works. This may be the essence of the problems...

 

[SaSaSushi]

If you want the problems you have to end, UN-fuse the fusion drive into separate SSD and HDD. It's not really that difficult to do.

Not sure about the OP feels, but that's definitely not even a consideration for me, regardless of how easy it is to do.

There is also the possibility that it _cannot_ be "fixed" due to how fusion works (at the "block level" rather than the "file level", if my understanding is correct). This is unknown and remains to be determined.

Oh, rest assured it will be fixed, regardless of whether that is with an OS update, a firmware update or a product recall.

 

[Bear]

...
There is also the possibility that it _cannot_ be "fixed" due to how fusion works (at the "block level" rather than the "file level", if my understanding is correct). This is unknown and remains to be determined.
...

Disks don't know from filesystems. It's all bit, bytes and blocks to them. This is a problem in Mavericks and not Mountain Lion - that tends to point to a software issue. There's a possibility it's a firmware issue and almost no chance it's a hardware issue.

In any case Apple will do the right thing when they diagnose the problem and find the root cause.

 

[Strikerblob]

This seems to be Maverick issue but got this issue fixed with "Boom" app for now. With Boom running with USB audio devices connected, i get no audio issues and it also gives my system good volume boost as well.

http://www.globaldelight.com/boom/