The TV that was connected to the audio system was unfortunately killed by an electric shock some months ago.
When I replaced it with a new one, I found out that the CEC function doesn't work anymore, no matter which TV I hook up the system to.
However, I should note that there is a picture from the device. I've confirmed it's not the TVs, because my Chromecast controls them just fine.
I found the service manual for the device and disassembled it, but there's nothing immediately obvious.
I've also tested the resistors near the HDMI port, all of them have tested with the correct values.
My only guess is that it could be either a capacitor (I'll be testing them tomorrow) or the HDMI port itself?
However, if it's neither, I'm not sure where to continue from there. Could anyone give a tip? Thanks!