zteecher :
HDMI cable from projector to Roku 3 (perfect picture but no sound) - Of course because the projector doesn't have speakers!
HDMI cable from projector to Bluray player (perfect picture but no sound) - same as above!
S video cable from "HDMI to S video" converter box to receiver (no sound) - You made no mention of this box previously!
RCA cables from "HDMI to RCA converter box" to receiver (no sound) - Again, You made no mention of this box previously!
Thank you for the response.
What you need is a receiver that has HDMI inputs. Then you run all SOURCES to the receiver with HDMI cables (BRD, Game Console, Roku3, AppleTV, etc)
You run an HDMI from the Receiver OUT to the Projector.
Connect your speakers to the receiver, and use a custom remote, like a Harmony remote, to control it all.