Yesterday I had a session with MADIface USB as a main soundcard and UFX as a secondary.
UFX was there in order to provide an analog input for talkback microphone and synth in the control room
and also to provide feed to control room monitoring speakers.
My DAW is Cubase 7 64bit and OS is W7 Pro 64bit.

Both cards, with latest drivers, were connected simultaneously via USB2.

After a while of recording the TotalMix FX 1.12 of MADIface just froze.
All the meters stopped updating.
I could press for example Talkback which lit up normally, but the function didn't happen.
All the routings worked during freeze and MADIface patched audio back and forth normally, i.e. freeze didn't disturb artist.

TotalMix FX with UFX selected worked normally.

During the session I didn't come up with any other solution than just unplugging and the plugging MADIface back again.
Then it worked for sometime just fine.

I changed USB cable and rebooted the computer. I didn't have time to try another USB port.

Any ideas what might be causing this behaviour?