My Receiver's bass & treble controls aren't responsive as when new?

[Freeman1962]

I have Sony STR-GX67ES receiver where the bass sounds like there is too much of it and is muffled for what I would consider normal for it's setting. The treble sounds lower and muffled than it should be also. Both settings are at their middle point, 0. When I turn either knob, the response I get is not as animated as I would expect from them. Does anyone know what might be causing this? The receiver is circa 1992? I thought maybe the computer chip, it is a dolby pro-logic receiver, might need to be reset but I cannot find any information on the manual on how to do this. Any information is greatly appreciated. Thank you.

 

[elnaldo]

I've seen exactly this same problem (loud bass, tammed highs, controls having little effect ) in 2 totally different amplifiers, and in both cases it was dirty loudness and "high filter " switches. Cleaning them or just pressing them several times solved the problem. But they were analog amplifiers, no digital controls...

I hope this helps.

 

[Freeman1962]

Thank you for the information. Will clean the loudness and high filter switches and, hopefully, this was the problem.

 

[Mitkraft]

This sounds like a perfect case for Deoxit. Do a search here for threads with "Deoxit" in the thread title and you should find the one that walks you through using it for this exact purpose. Basically the pots and switches get dirty and have corrosion causing the deficiencies you are hearing.