Pioneer VSX 55txi subwoofer thump

[i8asloth]

Lately when i turn on my receiver and also when i change the audio source on it i get a thump out of my subwoofer. Pioneers suggestion was that it may be a bad sub pre out and i would have to take it into t a repair shop...this unit is no longer under warranty and the repair shop wants 50 bucks just to look at it...Any ideas on what the problem might be
thanks

[JGrimaldi]

First, check your cables and connections. If they're all OK, open it up and take a peek. Look for anything that looks loose or burnt, or any loose objects. Other than that, can't tell anything without make/model.

[JGrimaldi]

Also, see if it still thumps if you turn the gain all the way down before powering off. If not, the problem is not in the Sub, it's behind it somewhere. Probably in the amp.

[Guest]

Do you have the amp volume down when you turn it on or change the source