I've come across these before. the electronic volume IC is quite notchy and
not very linear, but I presume your problem has got worse over the years?
I have a service manual (paper) which I could scan/send if you need. I
suspect the chip myself. I've had many more problems with the input selector
and graphic Ic's on these over the years.
contact me on service at wilkinsons dot tv

andrew

"Mark D. Zacharias" wrote in message
...
The volume control IC is bad and needs replacement, or else an IC which
shares the volume control IC's data pulses could be leaking into the audio
path.

Mark Z.


wrote in message
...
Greetings,
Fixing this thing for my sister as a favour.
The volume control is digital and as one pressed the buttons for
volume up or down you can hear the steps coming through the speaker.
It sounds lke static pops.
I have looked through the circuit and haven't found anything yet.
Thinking of targetting the chip responsible for volume control (if I
can find it) and maybe adding capacitors to damp out the pops..
As this unit it old could the capacitors inside have dried up and
created this popping sound?
Any other parts that may be responsible?