Hello guys

I'm experiencing an annoying issue (it seems that its since  2,9 update but not sure)`

while playing, the output on the left channel just disappears and is replaced by a white noise...

no matter playing a song in Itunes or a project in Logic

I have an switched off the RME , that changes nothing...  must reboot to fix... and it comes again after  a random time

I have also a Alesis master control connected: switched on or off, it doesnt change anything (if the problem shows up, switching off the Alesis do not fix the problem)

Anybody can help?

thanks a lot

osx 10.6.6
RME last firmware, last drivers
Logic Pro 9.1

Kader (Fr)