Hi this sounds typical of a "cold solder joint" in the solder around a component in the area concerned with that channel. These are very difficult to spot.
If you want to repair yourself - buy one of these - Lighted Microscope 60 - 100x
And read this - Spotting a cold solder joint
Once found, the solder should be melted with a soldering iron, while a little flux is applied.
Answers & Comments
Hi this sounds typical of a "cold solder joint" in the solder around a component in the area concerned with that channel.
These are very difficult to spot.
If you want to repair yourself - buy one of these -
Lighted Microscope 60 - 100x
And read this -
Spotting a cold solder joint
Once found, the solder should be melted with a soldering iron, while a little flux is applied.