Apple launched Mavericks and a slew of new computers at its Fall event in September, but now it appears that owners of 2013 MacBooks may be affected by a bug in the new OS that mutes all system sounds after they resume from sleep. Threads are cropping up around the Internet with users complaining that their devices have no sound after resuming from sleep and aren’t able to enable it. There are also reports that there is a background process gobbling up CPU after resuming from sleep that could be related. In system logs, users are seeing errors such as: 28/10/13 03:46:27,000 kernel[0]: Sound assertion in AppleHDAController at line 5460. We’ve run into the problem on 2013 MacBooks here at The Next Web too and everyone we’ve asked has run into the same problem at least once since upgrading.