fender stage 100 combo no volume

[summervulture]

so, i decided to stop using my stage 100 as a table.
i stopped using it around 6 years ago after i acquired better equipment, but it was also giving me a small input problem.

about a year ago, i blew a speaker in sunn cab i was using, so for a quick fix, i took the 12 inch celestion out of the stage 100.
now, after not having equipment at my apartment, i thought it'd be a good idea to put in a 15 inch eminence speaker and fix the input problem.

i hear nothing out of the speaker except for a very, VERY, low fuzz that changes pitch when i turn the volume knob.
any ideas? could it be the input, or did i not put the speak in correctly?
i'm not really a tech-savvy person, but i know basics.

[Chuck H]

If the amp was giving you "input problems" (not sure what that means, cutting out like a bad connection?) that may still need attention. Other than that I would say that any amp that sits for a time can develop oxide on the switch, pot and jack contact points. Try cleaning the jacks, switches and pots. All of them. Effects loop, input, output and any others. Put a little contact cleaner on a 1/4" phone plug and plug it in and out of each jack several times. Spray a small amount into pots and switches and operate them vigorously. Ideally you would open the amp up and actually use a mild abraisive on the jack contact points themselves. With "switching" jacks that may be the only way since the 1/4" plug may never actually touch the switch contacts. If they're sealed jacks then it's hard to tell if the jacks are the cause without replacing them. It's a good place to start though and won't cost much.

[Jazz P Bass]

Plug your instrument into the FX Return jack.
If you have volume now, the problem is before that jack.
If you run a cord from FX Send to FX Return, that will bypass the normally closed contacts on the jacks.
If this helps, then you have a cruddy jack.
If it does not help, then the problem is in the preamp.
Most likely a bad solder joint on the input jack.
Then again, if the amp fell over at any time, face first with the cable plugged in the jack, well......