I have had my EP500 hooked up via the line input to a Yahama 659 for almost 2 yrs w/ no issues. Recently added 2 surround back speakers and a BluRay player via analog inputs & optical to my receiver (this is the only thing that has changed w/ my system). Now when I hit a button on my TV or satellite remote control, even if the receiver is in standby, I can hear a small "thump" come out of the sub.

I also have a PS3 and Satellite box w/ optical lines plugged into the receiver. Nothing else is connected. No video runs thru the receiver. Everything sounds great when I am simply listening to movies, music, TV, etc.

Any ideas what could be causing this annoying noise????

I would start by disconnecting each component one at a time until the thumping stops. Then you will have to figure what about that certain piece is making the noise.

Try unplugging the EP500 for about 10 seconds then plug it back in...For some reason my EP600 thumps now and then after it builds up a charge or whatever, once I unplug/plug it back in it goes away..

I encounter the same noise from my 500 the odd time when someone is moving it to make adjustments.

never mind.....

Yep, some walkie messing around again

My EP500 tends to make repetitive thumping noises after a dip in power (brownout). The only way I can stop it is by flipping the master power switch off and then back on. The thumping loudness is not affected by the volume dial.

yep, I get mine during lightning storms.