It sounds like the 3v lithium battery supplying the microprocessor needs replacing – quite a common fault. It is soldered in place hence requires some technical knowledge and soldering skill to replace. Have a search of this and the archived forums for advice and/or join as a silver or gold member to download the service manual.
Hi, Could you explain what this “Code” message tells. I have had several BM3500/4500 with faulty backup battery but they still work they just don’t remember the settings after power has been off. Some BM3500/4500 have trouble with the Mute relay on Speaker 1, do you have the same problem when you connect your speakers to Speaker output 2? Can you operate the Beomaster via the front touch buttons?
A Beomaster with a bad backup battery can act up in different ways. If nobody knows which settings and what content is being stored in memory, things really get quite unpredictable.
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