Our old BT Freestyle three-handset plus answering machine is dying, with its displays failing so only part of each number is visible. We bought a new BT7610 Trio to replace it, but we hear a buzzing sound when we use it – our callers don't.
I tried BT Quiet Line and the buzzing (mains frequency I think) remains audible until I move within 1 metre of the base station. I spent the morning unplugging everything (computers, Devolo homeplugs, router etc) and plugging the phone into the test socket – no difference. The buzz fades in and out at about 10-second intervals but it's not acceptable for daily use even though we like the 7610 otherwise.
I am returning the phone as faulty, because our old unit still works perfectly when replaced. From the net, it seems that background buzz is not uncommon. Has anyone any ideas, please?