Display contrast not working, Elite All-in-One

[FarmerRaq]

Hi all, hope you can help.

For some time, the display on my Elite All-in-One has lost contrast.  Hard to explain but I will try.  Basically, the contrast setting is malfunctioning so that you can't see the differentiation between shades of grey (for example, slider bars, rulers, pop-up boxes, shading in tables, shading on task bars).  I've attached some photos:

This is a photo of a document dragged to show on both the secondary HP monitor (left) and the HP All in One (right).  Note the loss of contrast on rulers and taskbar.

All in One on right - no contrast in taskbar or ruler

This is a photo of a document open on the secondary HP monitor:

This is how the screen should look

This is the same document displayed on the All-in-One (can't see watermark, contrast in taskbar, ruler settings etc.):

This is how it looks on the All-in-One (can't see watermark, taskbar contrast, rulers etc.)

This is a marked up screen grab from the HP Monitor:

This is how it should look.

This is how it looks on the All-in-One:

This is how it looks on the All-in-One.

I have tried the following fixes:

- diagnostics through HP Support Assistant (all passed)

- reset monitor to factory settings

- adjusted contrast on monitor settings

- downloaded and installed all current drivers from HP website - this corrected the problem until the minotor went to sleep overnight - on sitting at the PC again this morning, the problem is back.

If I take a screenshot of the All-in-One display and move it to the attached HP monitor (which is working fine) the contrast is there, so it's a hardware issue, not a software issue.  It's very frustrating as I work in design and I need to be able to see the subtleties in shading.  Aside from that, it makes navigation and using software difficult as you can't see guidelines or windows clearly.

I wanted to contact support by email so I could attach photos demonstrating the problem but can't find an email address.

I noticed that at least one other comment on this community page was for the same problem, but the solution was to reinstall the latest drivers, which I have done.

Any thoughts, or email address for HP Support?

Many thanks, Raquel