Music Studio and UR242 Channel 3 & 4 issue


when connected Music Studio 2.10 on an old iPad (Retina display with 30-pin connector, IOS 9) with Apple camera kit to UR 242, I have sound on all 4 input channels.

But when I try with an iPhone 5S (IOS 11), lightning Apple camera kit, I have sound only on 2 input channels (4 channels are recognized but only the front UR242 input get sound).

When using Audiobus 2 on iPhone, i have sound on 4 input channels.

When using dspMixFX on iPhone, i have sound on 4 input channels.

Have you any ideas why it doesn’t work on IOS 11 with Music Studio ?


Thanks for the detailed bug report, that’s really odd!
Since 4 channels are recognized, it means that iOS reported 4 channels to Music Studio and Music Studio is probably receiving on 4 channels.
What I can’t explain is why channels 3+4 are silent. Please try the following:

  • Unplug all hardware and quit all apps
  • Restart your iPhone (hold the power and the home buttons for 10-20s until the Apple logo appears)
  • Plugin the UR242
  • Launch Audiobus first
  • Then launch Music Studio
  • Check if inputs 3+4 receive a signal

I’ve done other tests, but I forgot to restart with power and home (I restarted with normal power off/power on)

I uninstalled Audiobus 2, retest without success, then I installed Audiobus 3 and retest without success.

But if I use Audiobus3, I can route channels 3&4 to MusicStudio and it works (I will use this setup).

Another app, TE Tuner has the same issue (Channel 1,2 works, Channel 3,4 doesn’t even if I can choose them in the App Preferences).

So maybe it’s an IOS 11 issue.

Other apps like JamUp or AmpKit doesn’t allow to select channels 3&4.

I will retest with power on/off with home/power buttons.

Have you Steinberg UR interfaces to do some other tests ?