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It seems like there has been repairs before I got the device and I think somebody used the worng solder / flux. There were many flux residues which seemed to be corrosive! I cleaned up the PCB with a lot of isopropyl alcohol and a toothbrush and repaired three traces with a piece of wire and now it seems to work once again, lets hope it won't die again after assembling it
Regards
Lukas
It seems like there has been repairs before I got the device and I think somebody used the worng solder / flux. There were many flux residues which seemed to be corrosive! I cleaned up the PCB with a lot of isopropyl alcohol and a toothbrush and repaired three traces with a piece of wire and now it seems to work once again, lets hope it won't die again after assembling it
Regards
Lukas