Display dimming unless plugged in

[Brad]

Hi everybody
I just received my pinephone beta with convergence pack which is the latest they offer with Manjaro and Plasma Mobile. 

Things have gone perfectly with it.  I have updated and upgraded everything perfectly but for some reason at the end of the day yesterday the display goes to black unless I hold my finger on the display.  Initially I thought that it may have been related to low battery which was at 15% so plugging it in fixed it.  But today with full charge the display shows itself only momentarily and then dims.  If plugged in its fine.

The "display brightness" slider that I access by dragging the screen down will slide itself to left and dim the display.  If I drag it to the right to full brightness it stays there while my finger is on it, if I remove it the slider slides back to left and gives a black screen.

I don't that this is related to an update as the phone was fine for a while after I updated and upgraded. Its just went like this for seemingly no reason.

Can anybody possibly suggest a way forward here?

Thanks for amy help.

[Brad]

I should add that I have also checked the display setting and both lock screen and screen turn off are set at 15 minutes.

[megous]

The phone has an ambient light and proximity sensor in the top left corner. It may not be working correctly.

Maybe just disable the automatic brightness adjustment in your distro?

[acrux]

I should add that I have also checked the display setting and both lock screen and screen turn off are set at 15 minutes.

It helps if you search the forum
https://forum.pine64.org/showthread.php?tid=13744

[Brad]

Thank you for that reply and the link.  I did search but was unable to turn anything up.  That has however fixed the issue for which I am very grateful.

Thank you for taking time to reply.

[Brad]

Thank you for the reply. I didn't have any luck searching first time. But this did appear to be the problem and now its all good.

Thanks again for taking the time.