On 02/04/2019 02:43, Tom Del Rosso wrote:
I had never heard of this problem before, but it's good to know.

https://www.youtube.com/watch?v=wrNqM2GO7IU

Thanks,

I have exactly the same issue on mine, and now knowing that its just a
spec of dust on the diffuser, is explanatory enough so I'm content
enough to leave this Dell as it is. It's not as the LCD is broke and
colours are coming out wrong, or stuck pixels etc...

--
Adrian C