Using Windows 10, 8 core cpu with 16gb ram.  I haven't had this issue until today (so it has been working fine in windows 10 up until now).  For some reason in the project I'm working, I can only get audio playback when global fx is bypassed.  As soon as I have fx on, I get no sound (but the meters are still going, so there is signal).  I'm not aware of changing any settings that would cause this, but maybe I did.  Can anyone help please :-)

Ok, so never mind I guess for now?  LOL.  I closed and opened Platinum about 10 times, rebooted the PC, turned the sound card on/off a bunch of times.  None of that fixed it... until the 11th time.  Now it works and I didn't change anything.  Computers have a mind of their own, and I think mine is plotting to kill me in my sleep.

Hi. Which version of SONAR do you have? I have have periodically had this on earlier releases. Is it the same with other projects as well, or only on a specific project?
Best of luck.

Perhaps some long running scheduled task in the background, or a maintenance thing, or long-running complete virus scan of the world.
 
I think it is these 'unknown nightmares' that tend to gray and thin our hair the quickest, though a hard drive failure is always good for ripping some out by the roots.
 
Glad it came back to its senses.  Maybe it was just having a moment.
 
Bob Bone
 

Pretty convinced it's audio interface and drivers or perhaps chipset drivers and BIOS. Update them all.