iPad Air 2 - iOS 8.1.2
Steinberg UR44 in CC Mode - v2.11
Cubasis 1.8.3 (using Amplitube FX inserts from IK Multimedia latest versions)
dspMixFx 2.1.0
Apple Camera Connector (Lightning Type)
Basically all works fine for a while guitar effects and all, then all I can hear through headphones is the direct monitor clean sound from UR44. I’ve checked this also while using the dspMixFx App i.e. the level to the DAW is working along with Master level then the DAW level just stops while the Master is OK. Re-booting the iPad Air 2 solves the issue until audio dropout occurs again usually after a few minutes later.
I also have Cubase Pro 8 on Win 7 64bit which doesn’t have any problems like this with the UR44 so I’m assuming this is some kind of UR44 CC Mode driver handshake issue with the IPad Air 2.
Please check if the problem appears when using (a) no effect and (b) a different insert effect than Amplitube.
Does the problem persist when using the available guitar amp classic models (DSP effect) of the UR44 (via dspMixFX)?
I did the tests you suggested firstly direct hardware using dspMixFX all is working fine, with and without Yamaha FX.
The problem does appear to be with the Amplitube inserts when you exit Cubasis after turning monitoring off within Cubasis, and re-open Cubasis a few minutes later and turn monitoring back on the Amplitube inserts loose their connection with the signal path/audio bus somehow. I have proved this by having an Amplitube insert on one track and Steinberg Amp Sim on another, the Amp Sim will still work after the above procedure but Amplitube inserts will not. The problem can only be resolved by removing/re-inserting them in the track or rebooting the ipad.
One other question I have is the direct monitoring signal is always present and Cubasis does not have the option to turn it off (unlike Cubase) so you actually monitor the latency free UR44 hardware signal and the processed latent DAW signal at the same time which is a bit off putting. Could turn off Direct Monitoring be included in a future update?
I’ll try to get in touch with the guys from IK Multimedia to check where the problem could be related to.
Regarding direct monitoring:
You should be able to de-activate direct monitoring in Cubasis simply by tapping the corresponding speaker button on the track in the track list or in the mixer.
If I set up a guitar effect in dspMixFx, when I open Cubasis and arm speaker monitor icon whether in track list or mixer view I can still hear that hardware effect (with no effect set up in cubasis), and as you say this should not be the case.
Use the following steps to work with the cubasis monitoring function and the UR44 interface:
Send the input signal eg. Guitar to UR44 input 1+2
Open cubasis project and create audio track “A” and assign UR44 input eg. stereo 1+2
Activate monitoring button on audio track “A” to rout the guitar signal to dspMixFX “DAW” channel
Launch the dspMixFX UR44 App
Result : Guitar signal is available on dspMixFX " Analog 1+2 Channel, DAW Channel, Master Channel "
Mute the dspMixFX " Analog 1+2 Channel"
Go back to cubasis and deactivate the monitoring button on audio track “A”
Result : Guitar input signal is not audible on UR44 Headphone 1
activate the monitoring button on audio track “A”
Result : Guitar input signal is audible on UR44 Headphone 1
Short description :
The cubasis monitoring button route the signal direct to the UR44 “DAW” Channel.
So you can mute the dspMixFX analog channel 1-6 to use the cubasis monitoring function.
Anyway,
all dspMixFX effects on analog channel 1-6 are audible on the " DAW " channel and recordable in cubasis.