MR816 CSX disconnects from Cubase

Hi guys,

For the past couple of months, I’ve been experiencing a strange problem with the MR816 CSX.
Not always, but quite often, a Cubase 6/6.5 project would open with no sound coming from its 2-Bus channel.
Yet, in the VST Audio System tab, I still have the Yamaha Steinberg FW driver selected.
Only after I switch to the Build-in Audio Driver and then back to Yamaha Steinberg FW driver, the sound re-appears into the system.
Lately however, switching back and forth between drivers is no longer enough. In order to have the Stereo Out active (and sound out of Cubase), I need to re-boot Cubase.
Occasionally, the Steinberg’s driver in Cubase just disappears in the middle of a session.
The latest occurrence was while I tried to open a Monitor channel under the VST connection tab.
Cubase just auto-switches to the Build-in driver and the MR816 front pannel light’s starts rotating, until I reboot the audio interface.

I reinstalled the Steinberg’s drivers several times. I re-installed Cubase. I erased and re-build the Preferences folder.
The FW bus is used exclusively by the MR816CSX. No external HD has been daisy-chained etc.

This slows down my work considerably and I can no longer treat it as just an annoyance.
I would appreciate very much anyone’s input as to the possible cause of this persisting problem. And a way to resolve it.

Thanks in advance !


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iMac OS X 10.6.8 2.93 GHz, Intel Core i7 16 GB 1333 MHz DDR3
Yamaha MOTIF XF8
MR816CSX
Dangerous D-Box