Why is my amp doing that?

[reco]

hey yall!
my fender princeton 112+ is losing volume!
It has a ok level on the dirty channel but on clean it wont cut. it too quiet. Im not using it but the other guitar player in my group is till he gets a new one(hes getting a JC-120.... lucky dog). Im ok for now I have a peavey clasic chorus, but would like to know if anyone would know why its doing this.
thanks.

 

[Stan Williams]

Switching jacks

If your amp has an effects loop or preamp out and poweramp in jacks, that could be the problem. You would not believe how many of those i repair. The sound will go from normal to weak and thin. Patch a cord from send to return to check. If you don't have effects loop, you may have bad solder joint or circuit trace.
Thats it !

 

[reco]

Hey
yeah I will check it saturday when Im at our rehearsal space.
It does have a loop so......
-Reco

 

[reco]

Them dar Amps is weird, stuuuufffff!

OK,
I tried the efects loop thing....didnt werk.
Tried plugging in my head phones and got sound out of one phone at first then I turned up the volume and got good sound out of it.
Then I unplugged the phones and the amp was werking just like I should loud and clear.
Any Idea?
I think it may be the phones jack.
Thanks
-Reco