Sansa clip screen dim

Sansa clip Screen dim despite recharging

I have one just like that, changed the battery and it didn’t fix it. It gets brighter when it’s on AC power, and goes dim immediately when unplugged. I think the backlight inverter is going bad.

Would be interested to know what causes this. I’ve had a Clip+ since they first came out and used it all the time. Only recently did I experience the dimming screen. Pressing on the screen would sometimes brighten it but what really worked for me was this. When dim if I grabbed the top left and bottom right corners and gave a very slight twist the screen would brighten again for quite a while.
At some point it would dim again but the twist would bring it back. Seems if a connection is loosening like maybe where the ribbon cable meets the board. Traces too small to reflow the solder on this board.