After running PBX in a Flash (PiaF) in a virtual machine for a few days, I had a couple issues:
The system would generate an occasional message "TSC appears to be running slowly. Marking it as unstable." This issue did not keep the PBX from running.
Voice quality was sometimes jittery. In a call, it would sometimes "cut out" (like a bad cell connection). In voicemail, even listening to the pre-recorded prompts, there was frequently some garbled-sounding audio.
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