Midi Interface problem since OSX MAvericks Upgrade

I've got the same problem and it seems as if a lot of people are having the same issue..

Sorry no answer to the problem just want to mention I have the same issue using the m-audio mobile pre USB interface.

At this point hoping for Avid to come up with new drivers or Apple with an update to 10.9 which will fix it.

Mee too, same problem with m-audio mobile pre USB interface...

And me, m-audio pre USB stopped working has no out put through my mac, I haven't tried testing its inout yet, I hope that works else I'm stuck...

I have a somewhat similar problem.

I have an Edirol FA-66. I haven't tried MIDI out recently, but MIDI in is dropping some events, so I'm getting occasional missed and stuck notes / chords. The only music I've done with the computer since upgrading to Mavericks has been practicing with Pianoteq standalone; haven't tested any other software. I'm pretty sure my keyboard isn't at fault.

I'm having the same problem! I'm running a Mac Mini mid 2010 with Mac OS X 10.9 Mavericks and Garageband 10.0.1 with all the updates installed. Have a brand-new Behringer UMX610 keyboard controller and am getting ABSOLUTELY no output from this setup. The computer totally recognizes the controller, but no sound is produced. The keyboard's master slider changes the volume on the Garageband instrument, but no output is produced from any of the keys. Has anyone heard from Apple? Or has anyone reverted to Mountain Lion to see if that fixed the problem? Thank you.

I just posted about this problem with my mobile pre USB. I didn't see this thread. If anyone comes up with a solution, I'd be happy to hear it.

I just want to add my name to the growing list of people with a MobilePre suddenly decked by Mavericks. No input, no output. It's not even recognized.

I wonder if there's a file from Mountain Lion which could be moved into the System of Mavericks to repair this? Does anyone know how the MobilePre was recognized in 10.8? It didn't require a driver, I don't believe. It was just recognized as core audio.

All right everyone, I got this to work. I decided to see whether plain old plug and play would do.

Here's what I did.

1 Unplug the Mobile pre

2: place the application folder in the trash and empty the trash

3: go to the systems/library folder. Browse each subfolder in the library. (Preference panes, etc. Trash any file that has mobilepre USB in the name. Empty the trash each time.)

4. When you believe you've discarded all Mobilepre USB files, plug in the audio interface.

5. Go to Sound preferences and set the sound output to external device.

6. Test to see whether you've got your audio back.

If this works for you, please let me know. Thanks. Hope it helps.

I just got my mobile pre USB to work. Check out my reply at the bottom of this thread.

I had it too. You must completely get rid of the midi driver. wherever it is on your system (different for everyone) its either in apps, utilities, or downloads (or even other places, depending where you originally installed it from).

Then, search for the driver again online. install and viola. worked like a charm.

I didn't install a driver the second time. I just did plug and play.

Mobile Pre

I tried to follow the instructions but wasn't able to perform any of the suggested actions.

1. dont have mobile pre application folder (searching finder did not return anything matching mobilepre avid or m-audio)
3. no entries for mobile pre in systems/library folder.

Given the above it would seem nothing with mobile pre in my file system so I tried reconnecting mobpre usb however still no sound....shame

But I hope your instructions help others

Tjrdojo, let me be clearer. When I went in the systems/library folders, I didn't look for a mobilepre folder. I searched every subfolder. Especially check this folder: systems/library/extensions. Look for mobilepre or maudio files ending in .kext. Trash those. If that doesn't work, I wish you the best.

Thanks gonefrom10, sorry I wasn't very clear in my reply. I did go through the sub folders in ~/library which I can only assume to be the systems library folder. If this is correct then apart from not seeing any ref to maudio, mobile or .kext.

Am I in the correct library folder as there also does not appear to be a folder named extensions?