Well at least you could use an optical connection to carry DD5.1 from the player to the receiver. You might have to tell the player in its menu somewhere to not send the audio through HDMI but to use the optical digital connection instead. That won't give you lossless audio, but it will still be good surround sound.
I use a Sony BDP-BX57 (BDP-S570 equivilent) for my 3D bluray player.
The video is connected to an Optoma 3d-XL box, then from the box to an Optoma HD66 projector.
I am using optical out for 5.1. Everything seems to be working without any problems.
You might double check your audio menu options again just to be sure.
I am also using a Panasonic DMP-BD55 for 2D bluray that has analog outs for lossless 7.1