Indeed I have the complete 3500 Beosystem. It’s a classic understated B&O design and personally I favour this version to the shiny Beosystem 4500 which shares the same chassis and most functionality.
When I used to use the digital output of my old Beogram CD 3500 into a 5.1 receiver the sound would sometimes cut out part way through playing a cd. I hope yours doesn’t misbehave in the same way.