Hi,
I'm using an HP ENVY 700-060ea desktop.
Since upgradubg to Windows 8.1 I been experienced a delay of about 2 seconds in all audio playback. This includes system sounds and online videos. On youtube, the video will start and then the audio plays about 2 seconds later, making it out of sync. When testing system sounds, I press the 'test' button and have to wait about 2 seconds to hear anything.
I've already tried a system refresh, but this doesn't solve the problem. No system restore points are available.