Normally, with a MCL2AV, the volume level in a link-room can be up to 12 dB above the level of the main room.
So if the volume in main room is only 20, and the volume in link-room is very high,
my guess is is that there must be something wrong with the settings / setup.
If you want, i can send you the overview of the B&O recommended setup.
Is the following correct ?
- main room : BM5500
- link room : MCL2AV + MCL2P
Any other components connected ?