This is related to the new SDL audio backend and your 5.1 channel configuration. While I'll troubleshoot this, can you try setting your audio interface to stereo?
Yes, you were right. I switched my SoundBlaster Z card from 5.1 to stereo and it seems to be working now.
Hi FerrariMAF, can you tell me how can I get back HALL-9000 core and GlaDOS core back?! I accidently destroyed the car while I was killing some bitters, forgot to put those Items In main character inventory.