hi guys

i have a problem with my htpc - projector setup at the moment - headache headache ! * ggrrrrrrrr *

Equipment :
- Pioneer SC-LX85 A/V Reciever
- Compaq PC with Radeon 6670 with manual switcher (to switch output between TV and Receiver Projector)
- Projector Sanyo PLV-Z2000
- HDMI cable : HDMI v1.3 (from Receiver to Projector and TV) and HDMI v1.4 from PC to Receiver

All equipments were bought brand new

Problem :
the picture via the PC / video card sometimes dropped out, gone blank (black) for 3-5 seconds (sometimes i even had to close the MPC-HC player and restarted it), so i can continue watching the movie. movie is played via MPC-HC, using madVR.

tried different cables to no luck

if i connect the pc direct to my tv, samsung PS63C7000, it went without a glitch, picture never drops out, unfortunately it's not the case if i put it through the av receiver for the projector display

any ideas please ???

thanks