Sounds like a VLC problem
As much as I would like it to be the case, it can't be. Yesterday I had only Chrome running before closing the lid. Upon wakeup, quit Chrome and the core went idle (after ~15 sec). Today, neither Chrome nor VLC and the thread was stuck indefinitely, had to reboot.
I sent a bug report to Apple, hopefully they'll come back to me so that I can provide them with Spindump.txt and sysdiagnose.tar.gz.