Installed new Sky Q box yesterday to replace faulty one. Connects to a Sony Bravia TV and Sonos soundbar. All working ok yesterday and switched off before bed with Sky remote. Around 2:30 am was awoken to really loud sound downstairs - hissing and crackling like a giant speaker on full volume. It was incredibly loud - I thought the boiler had blown or something. Grabbed the Sony remote and turned it off and the sound immediately stopped. This morning when I had a look at things, the Sky box was stuck and wouldn't output to the TV at all and the Sony TV appeared normal but i-player and other apps wouldn't stream properly. Sonos speaker worked ok when tested with a Sonos app input. Eventually got everything to work by turning the TV off at the mains, which then allowed the Sky box to be reset/updated. Does anyone have any idea what the issue might have been? Worried it may recur.
