Hmmm, maybe the Option programming is lost... Try in standby: Sound 1 Store

What speakers do you use? Do they switch on, does the LED change from red to green?

Vielleicht besorgt's ihm mal einer genauso? Verdient hat er's... Schade, dass er den Stecker gezogen hat, echt schade....

Replace the smd caps on the drive, that's all. There is no need to use smd parts, standard caps are sufficient. Just replace them, nothing else. But clean the board with paint thinner, the acid of the caps may still be there...

The boards are different, i dont know wether 3500 and 4000 are exchangeable... never tried. But the focus/G2 unit is identical.

Yes. Original all the same. Newer parts have a different design, but still the same function.

That's not a easy job, you need some experience and at least a frequency counter and a oszilloscope. Or you are lucky: look for bad solderings, especially around the wire connectors. Check the heat of the chips. Try to set a known frequency with the MCP, notice the answer to the MCP, what frequeny is displayed.

Did you adjust the switches to: Auto? Speakerlink sends only a left or a right signal, not both like powerlink.

Why? A new relais is around 2 Euro... I'm not sure, the BC9500 has a 9V relais, but a 6V Type in seriel with 3 x 1N4002 diodes will also work... http://www.reichelt.de/?;ACTION=3;LA=444;GROUP=C33;GROUPID=3293;ARTICLE=8105;START=0;SORT=artnr;OFFSET=16;SID=25PZsngKwQARkAABPLDf0a9366f5d2f24c525449036a9f93b0e32

Das sollte genauso klappen, MX4000 und MX7000 teilen sich genau dasselbe Chassis. Softwaremäßig bin ich mir aber nicht sicher, ich glaube einfach nur reinschrauben...