TV does not display a picture or is mute on some channels
Wrong tuning information can cause some channels to stay mute, or black and mute.
Sometimes channels were moving to a new transponder, so you have to re-autotune. That will update the tuning information.
If that does not work, you can manually alter the tuning information.
The setting that is responsible for this problem is the AC3 PID which is detected wrong using autotune
The Problem is known and will be addressed with the new TV-engine