Here is the workaround: http://www.head-fi.org/t/630288/the-new-iriver-ak100-a-high-end-dap/2490#post_9135174
shotgunshane: thanks very much for the helpful link!
CraftyClown: we've experienced simliar errors, but it was due a corrupted file downloaded from HDTracks. If firmware version 1.33 is giving you troubles with playback of tracks you ripped from a CD, a temporary solution is that you could revert back to firmware v1.32 while we investigate the issue further. I apologize for the inconvenience this may have cause you (and everyone else).
I'll forward the issue to our engineering team and should have an official answer for you guys soon.