Split fusion drive or not?

Could you elaborate a little? I don't understand what your fusion drive has to do with the USB audio interface??

wallraff said:

The short version is that the fusion drive, creates interference with the usb audio interface on some imac models. Almost all people who owns imac with fusion drive and usb audio interface are having the same problem. Manufacturer blames apple, apple blames manufacturers, customer sits in the middle having the issue.
The problem seem to be somewhere in the fusion drive firmware because the crackling noise is related to when fusion drive is tranfering files to and from the ssd and analysing usage, which is the main function of the FD.

Click to expand...

Interesting. Hadn't heard of that issue until now. Anyway, this might help:

https://forums.macrumors.com/threads/1524745/

I dealt with the same problem. It will be resolved in the 10.9.2 update. Although it is of course possible to do, I would not advise splitting up the Fusion Drive. Hopefully the official 10.9.2 update will be released soon.

Don't do that!

There's no need to split your Fusion drive.

I had a problem with my USB audio interface on my late 2012 iMac with Fusion - and also on a 2012 MacBook Pro without Fusion.

The problem was with USB3 implementation and backward compatibility - and had been recognised by manufacturers (some at least, I use a Native Instruments interface).

The solution was to effectively downgrade the USB port to USB 2 by replacing the KEXT - make sure you backup the original before replacing.

here's a link to a forum discussing the fix (3rd post down)

the link to the kext file doesn't work any more though - but i had a copy of it still so i've attached it as a zip here

http://www.native-instruments.com/forum/showthread.php?169272-New-Retina-Macbook-Pro-USB3-0-Compatible/page12

hope it works for you...

[[ If I split the drives, will I be able to put the osx system and applications on the SSD and the rest of the files on the HDD? ]]

Yes -- it can be done.

[[ How can that be done? ]]

It will involve a little work and time.
And you'll need an external drive (which you ought to have anyway as a backup).

Here's what I suggest:
1. Use CarbonCopyCloner (free to download and use for 30 days) to create a bootable clone of your fusion drive to the external drive.
2. Boot from the external cloned drive.
3. Use Terminal to "manually de-fuse" the two internal drives. The commands and how to use them can be found online. It doesn't look to be particularly difficult, you just need to ascertain the "ID numbers" of the drives that comprise the "fused drive", and enter them into the appropriate Terminal commands to "break apart" the fused drive.
4. Use CCC to "selectively re-clone". That is, copy ONLY the OS, apps, and accounts to the internal SSD. Copy everything else to the internal HDD.

When this is done, you should be able to reboot from the internal SSD.

You should now see THREE drive icons on your desktop:
- Internal SSD
- Internal HDD
- External HDD

Do some test recording now.
Any better?

Remember, too, that at some point in the future Apple may be able to "fix" the problems with fusion and audio recording in the future.
If that happens, you can always "go back" to fusion at that time if you wish.

But I sense that splitting fusion (as outlined above) may help with your problems.

wallraff said:

Hi.
I am having a terrible problem using usb audio interface with my new imac 27" late 2013, and a lot of people are having the same problem.
...

Click to expand...

I read the issue is fixed in 10.9.2. If you can live running off the external HD for a few more weeks, it might be good to not muck with the fusion drive.

OP - you don't say specifically what your problems are.

I've assumed that is a general problem with your audio interface - hence my suggestion of the USB3 to USB2 fix.

OP is spot on and there are many documented cases of this all over the internet. I patiently waiting for my 2600 dollar computer to properly play through my DAC when a 200 dollar windows box can do it. I'm pissed off to OP!

I just purchased a new 2013 imac w/ a fusion drive, and I am having the same issue with my apogee duet 2. How do people know that .2 update fixes the issue? When will the update be released?

[[ I just purchased a new 2013 imac w/ a fusion drive, and I am having the same issue with my apogee duet ]]

See post #7 directly above for a possible solution.

[[ How do people know that .2 update fixes the issue? ]]

They don't. At this time, only rumors and speculation.

[[ When will the update be released? ]]

Unknown.
Could be several months.
Again, no way to know IF 10.9.2 will offer up "a fix".
If you want things working now, see reply #7 above.

Fishrrman said:

[[ I just purchased a new 2013 imac w/ a fusion drive, and I am having the same issue with my apogee duet ]]

See post #7 directly above for a possible solution.

[[ How do people know that .2 update fixes the issue? ]]

They don't. At this time, only rumors and speculation.

[[ When will the update be released? ]]

Unknown.
Could be several months.
Again, no way to know IF 10.9.2 will offer up "a fix".
If you want things working now, see reply #7 above.

Click to expand...

There are people who are developers who have 10.9.2 beta that says it fixes the issue. And as for how long probably a month.

Did 10.10 ever fix the iMac audio interface problems

Before I invest in an audio interface for my late 2013 iMac 27" with 3TB fusion drive, I'd like to know if the widely reported problem was ever fixed . some reports indicated that 10.9.2 might fix it. I know have 10.10.1 - am I safe ?