9 time out of 10, it's the mother board... unless you've already had this repaired.  My repair guy told me the original board had some issues with heat so if you operated your BM5 is an warm environment or the ventilation wasn't good, then it tended to fail.  The only solution I'm aware of for this is to get the part replaced by B&O. It could also be the hard drive - these fail too.  It's not hard to replace the hard drive if you have a backup of the old one.  If you search the 2012 - 2022 forum archive, you can find threads about doing this.  You will want to find the service tool which has been posted to the forum in the past.  This gets loaded to a USB drive and you boot the BS5 from it, and then can rebuild a new disk.  I guess I'd start here.  If the BS5 will not boot from the service tool USB drive, then it's probably the mother board that has failed.

Hi Stan, many thanks for your reaction! I do have a copy of all the files on the hard drive before the last crash. You think this would allow to identify the root cause of the problem? I see plenty of 'crashdumps' in the /Log/Crashes/BeoSound5 folder...? I'll try the boot from the service tool USB drive.

Unfortunately, I don't know anything about how to read the crashdumps or what they mean.

Today I managed somehow to startup again... first there was the same flashing as before (2/second?), I pressed the little button on the back some times, I turned the wheel (without clicking), I arbitrarily pressed the buttons on the front and suddenly there was a flash on the screen. After that the screen turned completely black, the red light went out and a little bit later it started 'SOS flashing'. Some time later it was fixed red and everything worked normally again. This will probably only last until the next scheduled reboot (on Tuesday or Friday). Any idea if such an 'intermittent' problem would either be hard drive or mother board related?

No idea and it’s probably quite frustrating… but… for about $150 you can install a new disk via a cloning tool and no computer is needed. Yes, if your motherboard is failing the $150 will be largely a waste of money, but it is one way of finding out.

When my motherboard failed, it failed.  There was nothing intermittent about it.  Then again, the last time I had a HD fail (in a laptop, not the BS5), it also was not intermittent.  In my experience, intermittent problems are often bad cables or bad connections (or most commonly software).  I did once have an intermittent problem with a macbook that was solved with a new cable to the HD.

The 'good' news is that most of the reboots succeed again... no idea why? A complete reboot takes more than three minutes, but with my keyboard attached, after ten seconds I know already if it will succeed - if the numeric LED of my keypad lights up. If it doesn't, the BM standby LED stays flashing 2/s forever. But I have never been able to launch the Service Tool. When I try the procedure described in the Service Manual, it has always resulted in a reboot failure. I'm also surprised to see a 'boot' and 'EFI' folder in the boot USB-stick? Is this okay, since these are usually partitions on a standard hard disk? I also got one bonus out of all my troubles. To analyse things more easily I installed VNC on the Beomaster and as a surprise this also functions in 'normal' mode and now I can watch the screen/cover art of the songs that are playing on my phone. No need to stand up and walk to the Beosound anymore, to know what is playing (I don't own a Beo5 :) Login to view image

That’s cool ? MM

Hi Luc Good idea to use VNC! What version have you loaded to the BM5 and to what file? Have you made the upload with USB stick? Thank you! Ruedi