Replacing selector knob

The selector knob on my integrated amp is suddenly making a lot of noise and not really letting the signal through.  Can this be fixed or can the knob be replaced with a better piece?The company is out of business, so going through them is not an option.
Might just be dirty pots. Try some Deoxit.
Is the "knob" bad or the selector switch? Replacing the switch would be a lot of work, so try a good cleaner/lubricant that has been suggested.
terminology: its the switch contacts that are flaky.  The know is the handle and is decorative.

The fix is likely electronics parts cleaner followed by a lubricant. but we do not know, you need to take it apart and also look for mechanical damage.

Its why i only design now with fully sealed relays under computer control.