RCF Art 310A Problem

[horgan]

Hi All,
First time poster here.
Im having an issue with an RCF 310A speaker,
Its distorted/muffled at all volumes, doesnt matter wether hot or cold.
Iv tested the amp module with other speakers and the problem lies in the amp module.

I ran a test signal through it and the volume control doesnt seem to change the signal on the bass output leads?
Q15 and Q16 are 5 pin transistors that I am unfamiliar with and (SAP16P and SAP16N), both seem to have 2 pins shorted.

If anyone has any suggestions or experience here I would greatly appreciate the help!
Billy

[horgan]

Also I apolagise if this is the wrong thread.

[g1]

Here are some schematics if that helps.

[horgan]

Thanks, have a bit of difficulty understanding some of it