Frontman FM25 DSP, low volume

[g1]

The RCA jacks are not outputs but inputs (aux in). They were basically so you could play along with a CD.
That is a good place to put in a signal (from a cd player or phone or something) when the fault shows up. It will help isolate the problem.
Try it when things are working right so you have an idea what kind of input level you need. Then when the fault shows up, see if the aux input is still working right or not.

[Enzo]

Your DSP card plugs onto the main board by a 20 pin connector. Two rows of 10 pins. Get under the card and gently pry it up HALF way out, then push it back down. ANy help? Your channels and all run through that card.

[SeBas]

The RCA jacks are not outputs but inputs (aux in).

Oops I forgot that its rca in not out. I also recall the signal going in is also affected by the same fuzzy or low output. But I will make sure to include that in anymore testing.

Your DSP card plugs onto the main board by a 20 pin connector. Two rows of 10 pins. Get under the card and gently pry it up HALF way out, then push it back down. ANy help? Your channels and all run through that card.

I am certain that I seated that P1 uDSP connector firmly down on the board when I reassembled it.

I did not clean the jacks but this time just shut the unit off while I wrote this post. I wanted to see if that down time, the amp had, would help and when I tried the power, it worked again. The volume was back.

I tried it today and the unit is quiet again, on both channel 1 and 2 and earphones. I'll wait for anymore suggestions before I open up the amp.
Instead,
now to open up that Peavey Kb300 and start a new thread on this beauty.

[Enzo]

I am sure you assembled it all right. But you have an intermittent problem. That DSP connector COULD be involved. By exercising it, we might expose a cracked connection, a weak connector pin, who knows what. Just poking it could reveal something. And yes, it might reveal nothing. But it takes five seconds. My advice to my trainees is "never think up reasons not to check something."

[DrGonz78]

Yup bust out a chopstick and start moving those wires around.

[SeBas]

|Some new information to keep this thread open and to help narrow down why this amp is not 100%

Been busy with no time to mess around with the amp. So previous to this thread it was low volume. Now its something different. I now have no volume on clean channel (1) and on the dsp channel (2) I got volume but it seems low on the amp types for two settings and the rest of the types seem to play okay. I will open it up today and start wiggling things until the volume for channel 1 comes back ( i hope). I am leaning now towards the dsp board or something leading into the dsp board.

[nosaj]

|Some new information to keep this thread open and to help narrow down why this amp is not 100%

Been busy with no time to mess around with the amp. So previous to this thread it was low volume. Now its something different. I now have no volume on clean channel (1) and on the dsp channel (2) I got volume but it seems low on the amp types for two settings and the rest of the types seem to play okay. I will open it up today and start wiggling things until the volume for channel 1 comes back ( i hope). I am leaning now towards the dsp board or something leading into the dsp board.

i would suggest building one of these https://www.diystompboxes.com/pedals/debug.html
To see how far signal is getting.

nosaj