Behringer pmp4000 keeps dropping an ouput channel while playing live!

In my opinion, due to the physical appearance of pmp4000 and pmp3000 look the same, it will most likely also have a common circuit and parts list (at least, most).
Usually Behringer (and all the manufacturers), with the same series / sequence, using the same circuit, the difference is the number of channels only. You can compare the parts list on PMP3000 schematic, with your PMP4000.
PMP4000.

PMP3000


You can download from this link.
http://elektrotanya.com/behringer_pmp3000_sch.rar/download.html
Hope this helps.
Regards.

You don't say what item of Focusrite equipment you are trying to connect or for what purpose. Most focusrite stuff has jacks with analog outputs for each channel that can be used into the line ins on the mixer and jack/xlr combos that can be used to take a signal to the focusrite box. Then you get the firewire side for the PC and digital outputs as well which will not be of use with your mixer.

This is a tough one because your LED for the Level Set is Illuminated, meaning that it sees a signal. With that being the case, the signal from the mic is getting from the input jack to the channel strip, but is not passing through to the preamp for that channel. So....either the channel strip is faulty, or the circuit going to the preamp is bad. As the other channels are probably ok, the trouble is most likely in the channel strip for Channel 1. Definitely have this looked at by a tech familiar with Behringer boards. If you can function without that channel, it will be cheaper than the repair, as the design of your board prohibits swapping out channel banks. I wish you luck and success with this issue.

If you are using the amp in stereo mode, then you will require a separate amp for the monitors and the input of that amp are taken using BALANCED TRS cables from the monitor jacks. If you are using the amp as MONO and monitor, then connect NO MORE than two 8 ohm speakers to the Speakon plug on the back labeled for use as monitor. Refer to your user manual... they have detailed photos of the connections. If you lost your manual, you can download another from the Behringer site. There are settings you need to do to configure the unit after connecting your speakers. The small slide switch has to be set to the center position for Main/Mon. Make sure it is centered as many people have had it slightlyu off and the system will NOT pass audio. You need to set each channel "monitor 1" level control to send the monitor signal to the MONITOR mixing bus. You will then use the MONITOR 1 slider to control the amount sent to the monitor. Be VERY careful of grounding the sleeve of 1/4 inch jacks that originate at the Speakon power amp outputs as the SLEEVE of channel A is the HOT side and you can blow the power amp for the channel... it is EXPENSIVE to repair.

only 2 effects can be used at a time. you assign the effects in your lil digital section in the master part of the board by turning the black knobs so the lit up numbers change to the effect you want then push the black button to lock it in. at which 2 of your aux's ( the last 2 i think its 5 and 6 ) control the SEND to your EFFECTS and the fader below the selections control the amount of effects goes into the MIX.

Things to check: You are using XLR mic cables... You have the speaker switch in the uppermost position A and B mains... the mute for that channel is off... For an SM58 the TRIM for that channel will be at about 3 o'clock to near full on, depending on vocalists voice strength... The CHANNEL fader will be at around -5 to 0 (75% up)... The MAIN fader will be around 50 to 80% depending on how big a room you are in. I assume the Peaveys are on separate channels IF they are 4 ohm speakers. The A and B outputs have a MINIMUM load of 4 ohms. With 4 ohm speakers you can get 400 Watts per side... about 250 Watts with 8 ohm speakers. DO NOT SET SPEAKERS to bridged mode... ALSO please read my tip on Fixya about a hazard of channel A polarity if you use 1/4 inch plugs on the ends at the speakers. The SLEEVE of channel A is the HOT, not the tip and grounding the sleeve can blow the channel A amp.

send me an Email [email protected] and I will see if I can get a hold of one for you

You would get about 200 Watts RMS per side using 8 ohm speakers. "Not much volume" is very relative. With the two 12 inch speakers you should be able to fill a 600 to 1000 sq ft room nocely.

There really ISN'T and "advanced" manual... Everything you need to know is in the user manual that comes with it... Service manual with schematics will not give you much you can use unless you are into electronics detail.

PLEASE read my tip about Behringer PMP mixers on here regarding a hazard if you use Speakon to 1/4 inch cables or adapters. Essentially, the sleeve, NOT the tip is the HOT lead for a speaker on channel A. Ground it inadvertently and goodbye channel A amp.

Be VERY careful of speaker leads with this amp as it is easy to pop a channel IF a speaker comes loose or shorts. Loop cables through the handlesto avoid cables being yanked out or breaking plugs.

If the fuse has blown DO NOT replace it without repairing the cause of the failure. You will likely do more damage to internal components. Take the unit for repair before applying power again. I have repaired many of these and first a failure occurs in one of the power amps... usually the A channel, then people replace a fuse that protected the power supply and that blows the power supply taking out another $30 of components and $200 labor. (they are hard to change) If the unit is under warranty, exercise your warranty immediately. There is a weak spot in the channel A power amp.

ALSO please read my tip on here about a hazard in PMP series powered mixers. It is in regard to using Speakon to 1/4 inch speaker cables... NOTE that the BARREL of a 1/4 inch speaker cable or adapter from the Speakon is the HOT side for channel A and if you ground it inadvertenly, goodbye channel A power amp!!!