Hi Postblank

My situation was almost identical to yours. I bought my Oberheim Matrix 6R at Ebay on May 21. This rack version is like the Matrix 6 but without the keys.

When I plugged it in, there was no sound except for the background noise - all the visual menu stuff was working.

So a lot of menu surfing and after reading this post today I opened it. I was this close |<->| to start pulling components out of the unit

However I behaved and located the round silver battery which I lifted just a little bit - I guess it was enough to disconnect it and reconnect it. Then by incident I noticed that the (grey) flat ribbon cable which connects the internal boards seemed to be not properly connected to the socket in the middle - so I fixed that.

Guess what - now the baby works and I am enjoying all the analog sound coming out of it.

I don't know what did the trick exactly but I suggest you try the same in this order:

1. There should be a wide flat ribbon cable in the keyboard version as well - it looks like a standard internal (ide/ata) hard drive cable. Make sure it is well connected to all the sockets. Turn on the unit again and try playing.

2. If step 1 was not successful, try lifting the battery just 1 or 2 milimeters and let it slide back into the original position. This is certainly worth trying before taking it out completely and searching the world for a proper replacement battery. Turn on the unit again and try playing.

I hope these simple suggestions help you and that you will post the results here.

Good luck
Flemming

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