Tube Screamer tone still not working

[MetalUpYerEye]

Hey guys I finally got back to my old Tubescreamer with the broken tone control. I replaced the 25k tone pot with a 20k (i actually found one!) and it had no effect whatsoever. I still get absolutely no response from the tone knob. it doesn't change the sound at all. i also replaced the .22uf tone cap and the knob still does nothing. i did however notice that when I switched the tone cap (it was a funky yellow film cap and i changed it to a brown film "chiclet" cap) the overall sound changed and got muddier. here's what i have

volume control works
drive control works
tone = broken

checked and resoldered all solder points from the JRC4558 through the tone cap, tone resistor, to ground including the pot lugs.

STUMPED! any help would be more than appreciated (how am i supposed to melt tubes with no tone control?   ((  )

[Dr Ron]

Is this an old pedal?

If so, I'd look for a broken trace - a crack in the PCB.
It may be the pot is not connected to the second opamp.

You can check with a multimeter set on resistance.

On the other hand, there could be a short with two traces touching
or two nearby pins soldered together by mistake.

There are two yellow tanatalum capacitors in the tone circuit.

[MetalUpYerEye]

Sorry about that - I guess I should've said "i'm back to my Tubescreamer with the broken tone" and left out the word "old..." This is a TS808 Clone I built about 2 or 3 months back, not a vintage one. I couldn't find tantalums at my local electronics store so I substituted these funky yellow film caps for the 2 .22uf tone caps. I had also originally used a 25k pot I ordered from Small Bear, but have since replaced that with a 20k I found at the electronics store and replaced the yellow film caps with 2 brown "chiclet" shaped film caps in an effort to get the tone working. Strange as it may sound - the circuit seems to sound as though the tone would be all the way up when I turn it on. Could there be a problem with bypassing the tone control (like its supposed to do when its turned completely down?)

[George Giblet]

From your first post, I'm with Dr Ron.

From you second post, perhaps you have a wire short between one two of the wires that connect the tone control to the PCB.

Whatever the problem I'd be checking for open and shorts of all the wires to the tone control.  In fact I'd be checking the connections all the way to the actual components those tracks go to (in the same vein that Dr Ron mentioned).

It shouldn't be hard to find buzzing things out with the multimeter.  You just have to do the leg work and be thorough.