How do I fix channels with no sound

Hi Elijah, check that you have assigned the channels to a SubMaster to the Master and that they are not in MUTE

Hola Elijah, controla que tengas asignado los canales a un SubMaster al Master y que no se encuentren en MUTE https://peavey.com/products/index.cfm/item/666/118299

Behringer products are notorious for odd problems over time and are not well supported by the company. You can attempt to take it to the shop for repair, but honestly i'd just replace it than spend cash on a repair only to wait on the next issue to crop up.

Step 1:
Check the setting of LOCAL CONTROL in GLOBAL mode.
Go to GLOBAL mode page 1 (Figure 1-2):

Move the cursor from the MASTER TUNE to LOCAL CONTROL. Setting LocalControl should be in the ON position.
When the setting is OFF,set it to ON (use dial TEMPO / VALUE or DOWN / UP button).
Go back to ARR or PROG mode,and play the key to check audio.

Step 2:
If in step 1, the sound still does not exist, then it is a hardware problems, and the possibilities are :
Figure 3, the section in red shading is a block may be damaged.

Figure 4 is a scheme. Parts that might be damaged in case of no-audio are:
IC 2,4,5 (4570), IC9 (78L05), IC6 (PCM69AU), IC 3 (5216).
Check also the transistors Q1-Q7 (This is the MUTE transistor, and this is most often the cause in case of no-audio).
If you can not fix it by yourself, then leave it to the experts.
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This could be fixed checking/changing the vol pot of the "B" channel, also i would highly recommend to clean all back switches, including Stereo/Bridge switch, which it should be outwards to operate in Stereo mode, let me know if i can help more.

That's basically normal actually...however it depends on which aux send you're using. If you use aux 1 for the effects, you can use the pre/post switch on the master aux 1 send to switch it to pst fader....now your mute switch should kill the effects as well. Aux 2 is good to use for monitors where you don't need to return them to the mixer.

USUALLY the Mute LED's for the switches ar operated by separate contacts on the mute switch an a resistor current limit for the LED. I could NOT find the schematic for this board, HOWEVER some Soundcraft brand mixers do NOT have illuminated Mute switches... Not sure about your particular unit.

Put a tiny bit of CRC226 around it to lube the button. Then CAREFULLY use a scalpel to encourage it to come up. Then put a little more 226 around it.

If your system has a mixer attached (I'm assuming it does) make sure mixer channels are muted when turning system on and off. Also mute channels when plugging in instruments. Muting channels will protect system from pops (and yes they are normal) You really should have someone operating mixer whenever you use system. For more info; contact folks at ALS (Audio Logic Systems) they're in Bloomington, Minnesota but contact them online and they'll help you through any problems. They specialize in House of Worship Audio.

Does the distortion ALSO appear when you listen with headphones? If not, the problem may be downstream. The driver for the mute control line to the mute transistors may have a problem. Make sure the mute is off.

Make sure the slider switch is set to the correct mode.

The TRIM controls must be advanced while the sliders are at 70%.

A common problem is to MISTAKENLY plug 1/3 inch input cable into the Effects Insert jacks instead of the inout IF you use 1.4 instead of XLR inout.

Make sure the channels of interest are NOT muted!