Have a pretty frustraing problem with the Kenwood HR507 exaserbated by the fact that I long ago lost the manual for this receiver.
Setup - have the digital audio connection hooked up from a Directv HR10-250 - the HD DVR - and component video to a Panasonic HDTV.
On the HD channels such as Discovery HD - the speaker diagram/icon that shows up on the receiver shows that all speakers are active including the rears. Also says LFE and Stereo downmix? Problem is that the surrounds are not working. I run setup on the receiver and indeed they are connected fine so it doesnt appear to be a wiring issue. Just not working with the HD channels I thought they would be working with when I thought they should be - showing on the display.
Don't forget that the surrounds are not necessarily putting out signals even if the indicator lights are turned on. If the signal source is not putting out any signal, your speakers will not have any sound at all.
For example on Dicovery HD on something I know is coming out in surround, its fine with just the Speaker A button active, but if I activate Speaker B, it cuts the Surround out. Bizarre.
Seems to be fixed, but its not ideal with the CLICK CLICK thing everytime the receiver changes sources.