I set mine to lock after 1 minute, and started recording. It did the same thing. After I unlocked the phone, the voice note recorder was still active and I could continue recording, but nothing was recorded while the phone was locked. I'm running 7.0.0.576 This is definitely an OS issue (I would think, anyway) Maybe others can try with their versions and see if maybe the issue has already been addressed.
Well, I'm only on BlackBerry 6, but that's exactly how it works with mine. Voice recorder stops recording when the phone locks. It kind of makes sense. How would you turn it off, or would it just keep recording forever until someone unlocks the phone and shuts off the voice recorder? Also, my encryption is on. Did you try it with encryption off?