Monoprice 4x1 HDMI switch and no surround sound (5.1) for PS3

[halcyon]

I have the following setup.

PS3
Hitachi 43" TV
Yamaha HTR-???? Receiver
other HDMI devices (Apple TV, DVD player, etc)

- MONOPRICE 4x1 HDMI Switch

For some reason, when I play Blu-rays off my PS3 with the switch, audio output goes through the HDMI switch and for some reason, it downgrades the sound to PCM Stereo. But when I play digital movies or games, it comes out as 5.1 surround sound. I've read forums that it might be an issue with handshaking between the TV and the HDMI switch but the fact I can get 5.1 surround for particular media is confusing me.

Any suggestions as to what's going on? Ultimately, I may have to do just route a TOSLINK cable from the receiver to the PS3 directly for 5.1 sound all the time. Anyone else having similar DTS or DD surround issues with the Monoprice switch? (I'd rather not buy a whole new receiver just at this moment).

[beuh_dave]

I think that you're right. It sounds like the problem is the HDMI switch (that's why I usually avoid them, so many problems). I don't know how to solve the problem, but you can try connecting the PS3 directly to the a/v receiver and see if the issue still persists. Maybe a try a different HDMI switch or buy a receiver with more HDMI inputs?