The reason your batteries may not work when you plug your lead in is possibly the plugging in of the plug opens the battery circuit so both supplies are not present internally at the same time.
Type: Posts; User: zimmer
The reason your batteries may not work when you plug your lead in is possibly the plugging in of the plug opens the battery circuit so both supplies are not present internally at the same time.
Sounds like your power pack.They are commonly switched mode power supplies, made in China and they, just, die...
Fresh batteries are actually better than running off AC. They are devoid of any line...