Onkyo receiver help

I have an Onkyo TX-600 receiver connected to a Comcast-Motorola HDTV cable box via an optical cable. When I change channels from an analog channel to a digital channel (like HBO) and the receiver detects the switch from PL2 to Dolby digital, I get a pop through my center channel speaker. Comcast came in and replaced the box and it still happens so they say it's the receiver. I sent the receiver to repair and the guy there thinks it's the cable box. Any one have a similar experience or advice? Thanks

While the box passes on the information from whatever channel you switch to, it's the receiver detecting the change and acting accordingly. IOW, it's the receiver.

I have that exact same receiver and cable box and I haven't noticed that issue. If possible, try asking a friend if you can borrow their receiver for a few hours. Try the same test on the other receiver. That will at least help you narrow down if it's the receiver or the cable box.

and have never notiiced the "pop" when it switches from PLII to Dolby Digital 5.1. But I must admit I'm using a higher end model. My 898 doesn't exhibit your problem at all. Showtime broadcasts in 5.1 sometimes drop in and out but that's it. Have you checked your cabling? How loud is this poping noise? If you've had both looked at I really don't know what to tell you other than cabling or possibly grounding.

Da Worfster :confused: