Intro: I spent several hours over the last couple days trying to figure out why there is no sound coming from the REAR speakers when playing 2.1 sources and such (streaming videos or music from online). 5.1 sound works in video games and DVD/Bluray, etc. There was no SPEAKER FILL option in the most recent REALTEK drivers. Quick rundown of my problem: 5.1 audio only worked for 5.1 output sources, not for everything. Interesting details: CONTROL PANEL > HARDWARE AND SOUND > SOUND, click Speakers (typical output source.... where the sound comes from), then the Configure button..