Behringer DDm4000 purchased in 2009. Over 2 years happy usage, but now it's got some major issues! The power supply seems corrupted as after about 2 hours use it maxes out the signal (ouch) and all the lights turn on, almost like it's "crashed". Obviously no good what so ever! A friend of mine has said it's something to do with a circuit that cannot be changed or repaired due to behringer not releasing circuit diagrams? I don't know, all i know is it's un-useable, yet annoyingly works fine for about 2 hours, this however in an average 5-7 hour gig useage is no good! Any idea's / help?

https://elektrotanya.com/behringer_ddm4000_mixer_sch.rar/download.html

If you wish to get some details; check the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Search the site by type in the "brand name" to your device; (Exclude the model number), in the "Search box at the top right of the display window of the Homepage" to get gathered related posts

Basically you've got no chance. Behringer are very protective and use proprietary parts so when out of warranty most of their items are throw away.

We always insist with our main suppliers that we get a repair and service manual at the time of purchase or we do not buy. This has stopped us buying on several occasions, We do still buy some behringer kit but only because of the three year warranty, we then sell before the three years is up. Most major manufacturers have no problem supplying the manuals however, and this has saved us a lot of money as we do some repairs in house. We do spend many 000s a year so maybe have a little more clout than some.

Try blowing out everything and check your contacts.

Is the number on the effects display still flashing? Can you select effects or is that section dead now? I've had occasions with my Behringer mixers where a bad ground or otherwise improper power supply seems to cause issues with the effects section but the board seems otherwise functional. It has definitely had me scratching my head a few times and is worth investigating.

Just use google search or go to this link:

http://www.behringer.com/assets/DDM4000_P0167_M_EN.pdf

The C23 part is a capacitor and the 7085 is more likely a 7805 which is a voltage regulator. The regulator is easy to find. For the capacitor, you will need the service manual to determine the value required. The main issue is that the leg of hte 7805 is lifted. This implies that the part was conducting more current than expected. This is an indication that the problem with the regulator is a RESULT of a problem, not the defect itself. I would not suggest replacing the power supply blindly as the root cause may beon another board. Just changing the power supply board may result in the same problem again.

I would suggest a trip to the repair shop to get a detailed repair estimate. The shop shouldbe able to determine whether or not the only issue is the power board.

Also, from the experience I have with Behringer units, the power boards are unique to each model.

Dan

Probably did major damage to the power supply. Likely the IGBT's are gone, the switching regulator and one or more of the 4 driver transistors and the speedup diodes and probably the ceramic charging resistors.

This will be close to your schematic: http://elektrotanya.com/behringer_europower-p0569_hca2400_sps1000_dpx_pmp-1280s_5000_sch.pdf/download.html

Scroll down to "get manual" and click on it to download. IGNORE other download links.

Repair of this is NOT for those unskilled in electronic repair. When restarting after repair, insert a light bulb in series with the power. You will need to use a step-down transformer to run this unit.

Freeze up is usually overheating, check your heatsinks and if the compound has dried up.