What signal is the HTPC Outputting via HDMI - it's going to have to be something the AVR (and Display) 'supports' - ideally it's going to be the native resolution of your Display and 60 Hz.
It's more likely your problem is EDID rather than HDCP - you may require an EDID grabber between the HTPC and the AVR!
Joe
It's more likely your problem is EDID rather than HDCP - you may require an EDID grabber between the HTPC and the AVR!
Joe