Cobra 200 control tensioner??

[Snelly]

Hi Everyone!

After purchasing our rv, i've got myself a Cobra 200 GTL DX (rev2) secondhand off ebay to replace the one that was missing. The seller said:

"There is a slight fault with this radio - but apparently it is easy fixed but I haven't tried. The main channel change knob slips when you change down frequency and sometimes misses channels (not all the time), but it is fine when you go up frequency and works as it should. A friend of mine had the same problem and he took the radio apart, and tightened up the control tensioner (whatever that is) and fixed his instantly. Alternatively, send it off to someone to fix it."

I haven't got the radio yet, its still in the mail. But has anyone heard of this problem and can I fix it?