Help troubleshooting sx-434

[jhnlfgrn]

Hi!
I have a Pioneer SX-434 receiver.
The left channel has a very low and distorted sound. It has gradually become worse. It started occasionally dropping out on a day to day basis but lately its always like that when I turn it on. It makes some scratching noise when I turn the volume but the volume dont come back. The right channel sounds great and when I put it in mono both speakers sound good and I can turn the balance all the way to the left and it still sounds great. I can't hear any distorted noise when in mono.

Should I suspect the volume pot or is it likely to be something else? (A couple of years ago I had all the caps replaced so they should be fine.)

If you think I should start to clean the pots, should I use an electrical cleaner without oil or with oil?

Regards
Johan

 

[nicholas2381]

Starting by cleaning the pots is a good idea. Deoxit D5 dissolves the corrosion that's likely built up over time. Spray some in the pots and then work them back and forth repeatedly (while the unit is powered off). Once you've sufficiently worked the pots, try the unit again and see if the problem has improved. If not, try the same process again. It can take some time. If this resoles this issue, then you likely want to use Deoxit F5 or a fader lube to ensure the carbon wafers remain lubricated.

 

[larryderouin]

Signal goes thru all the switches on the front. Do them also.

 

[jhnlfgrn]

Ok. Then I start with cleaning all the pots.

Thank you for the input.

/Johan