I recently came to a problem with my fairly new (half a year old) TV, specifically model QE55Q80T. The thing is, that after some time it's starts making high pitched noise, by ear I located it sourcing from the bottom of the TV, where the LED and simplified control button is located (most likely infra reciever for remote too).
To further specify: it happens only while turned off (and pluged in of course), it's gone immediately once turned on (or plugged out). Once pluged out and in again, comes back after a while, without ever turning it on. The only other electronics close to it is my router (don't think that has to do anything with it) and PS4 connected by HDMI the whole time (unplugging the console, either HDMI or even from electricity, doesn't seem to have an impact).
Do you have any idea what could I do, any troubleshooting ideas? Or just claim it as defected? Thanks in advance for any feedback.