jdmandist1,
It may be that the audio output is set to travel through the HDMI, and the hum is a residual signal that's not sending audio at all.
I believe you can either program the PS3 audio to output through the analog RCA or maybe even hook the television's RCA output directly to your receiver and run the audio from the HDMI to the television, and out through the RCA to the receiver.
Keep me posted.
--HDTech
using hdmi cable from ps3 to tv and rca jacks to recever it has loud hum also what are best settings for ps3

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