Nice system to inherit! B&O equipment is really designed to stay in stand by though clearly that does use energy (though very little with the modern equipment). If you can turn the speakers on first, that might make a difference.

We have a somewhat similar issue. We have an Avant with no other speakers connected to it. Recently I connected some speakers to it and when turning the system on or off a very loud pop occurs in the front speakers, but not the rear speakers. I spoke with a technician and he referred to it as a "DC pop" and knew exactly what part needs to be replaced in the Avant. I understand your pop occurs when the speakers first receive power, not when going from standby to on, but thought I would mention our similar issue.

Hi. I had that problem once when I cut powerlink cable and then taped it back together.  After I had it soldered, the problem stopped.

I used to turn my system off at the wall, but once my BL4000's power supply failed i started to leave everything on stand-by.

Obviously the pop isn't normal, but leave it all in stand-by in future. That's what i'd do, it prolongs the life of the power supplies, and for you makes things easier without the pop.

Try disconnecting the powerlink socket on the speaker you turn on.  Does it pop then, if so try a new power cable and socket to narrow down the fault?

As you have masterlink as well you may need to check the shields in the cable.  You could try your local dealer for a masterlink and power link tester as well...

These methods stopped the loud pops in our house. In my experience the BL8000's and BL4000's seem particularly sensitive to this problem..

good luck beoaus

I have a somewhat similar problem, but with a BC9500. It's installed at countryside, where it's quite common to get brief cuts or flickering in the mains power. If I just normally plug in the socket, I get a "medium" pop. But when there is a cut or bigger flikering the pop could be quite loud. It's a surprising, and not a nice one, sound, especially on the daytime, when you don't see the flickering.

When I'm away I tend to plug it off from wall, because the environment is also a bit lightning prone.

So is the popping in BC9500 normal and a small UPS is needed, or is there maybe some mains caps in need for replacing?

Pekka