Strange audio engine quirk - softsynth's sound disappears [SOLVED]

When I play my 88 key keyboard controller that I've had for 15 years, Platinum is turning off the audio engine sporatically. So far it's only happening with softsynths like Ivory and Superior Drummer. Maybe it happens with all soft synths, not sure.

I can be playing my Ivory piano with it's midi track as the active track. Input monitor's blue button is lit up. The transport is not moving, no playback, no recording, just playing the piano or drums. Then all of a sudden the notes are abrupltly chopped off and there is no sound. I can see the audio engine button  turned off. Nothing I can do will turn the sound back on except clicking on the audio engine button in the Transpsort so it lights back up or I can hit playback or record and then I can hear the piano or drums.

I'm not getting any other dropouts except in rare instances. I can have lots of audio and midi tracks with lots of FX playing back or recording audio and no problem, no dropouts except rarely. Yet if I'm just sitting there playing the piano, the audio engine shuts off. And it happens very often, maybe every 10-20 min. It happens also during recording midi, never during playback. I tried changing the default DropoutMsec from 250 to 400 - no effect. 8.5 certainly doesn't do this.

Any suggestons?

Gosh, did your buffer size get changed??? If I set mine to low it will play recorded audio and vsts ok but sometimes choke on realtime notes...I don't know! Good Luck! -Shawn

If you have Share Drivers With Other Programs enabled, try turning it off (Preferences > Audio > Playback and Recording). It sounds like something is hijacking your interface. Or there's a more general problem with your interface or drivers that's causing SONAR to lose the port. Any hardware/firmware/driver changes recently?

shawn@trustmedia.tv
Gosh, did your buffer size get changed??? If I set mine to low it will play recorded audio and vsts ok but sometimes choke on realtime notes...I don't know! Good Luck! -Shawn

Which buffer were you referring to?
Playback I/O buffer size = 512
Record I/O buffer size = 512

Under midi / Record
# of buffers = 64
Playback prepare using 500 buffers
 
Not sure why playing live midi into Sonar would be any kind of load or difficulty for Sonar.

dcumpian
If it is regular, maybe something in your PC is powering down the USB port?
 
Regards,
Dan

I checked Under Power Management and USB Selective suspend settings is disabled. Is that what you were referring to? I wish there was a diagnostic tool with Win 7, that would tell us what the computer is doing when this happens or at least give a clue.
 
Any suggestions?