Landscape Texture resolution keeps resetting in Landscape mode

Hello all, I have here another issue, however this has only recently shown up, Not sure why, but I am having an issue where when I am in Landscape mode and I try to paint my terrain textures like add some rock, I will note that my Materials will paint out blurred now or a lower resolution.
When I go into my Master materials I see the thumbnail views in the texture samples nodes for my Normal maps have gone blurry, by double clicking on the normal textures to open them in the unreal image viewer, the normal map then updates itself in the thumbnail and also in the scene, to the correct resolution, I hear then the fan of my laptop start to raise volume for a about a minute, but then it switches suddenly back to the blurry style again.

what is doing this, why is it resetting to a very low resolution and it only seems to do this with the currently selected texture type, like rock. Until you select a different texture type like sand, then the same happens for that one.?

I found something that shows a similar result happening when using the RVT, however I am using the default setup and have not enabled anything special, for this to be doing this, so I have no idea what it could be, but this is however now beginning to impact my ability to paint the landscape any further.

What could be doing this and how could I solve this, it almost makes it impossible to now paint when it keeps resetting the resolution.

I have noted that if I have my master material open also and I double click on a texture sample to open it in the image viewer it rereads the texture and updates the thumbnail as it should, as well as the scene, but at the same time the fan of the laptop starts to raise higher again, but then within a minute it resets back to the lower resolution again. It only does this with the current selected material slot, like say Rock.

What can be done to stop this from resetting like this and to ensure that I have the correct resolution at all times when I am in view, and painting the Landscape. The landscape is an 8129 size Landscape.

And I recently had baked a Mini-map the day before, but I don’t see that having anything to do with it.

Please let me know what you think could be doing this and what I could do or a setting to disable/ Enable, in order for this to be more stable when working on my Landscapes, since there is still allot more painting and modifications to be made.

Please see the image below, the top view shows what it should be, the lower image shows what happens when I go into Landscape mode and also if after double-clicking the texture sample, when it resets back to the low resolution, note in the normal map texture sample shown in the red boxes red boxes.

As you will notice that it only happens with the currently selected Texture, whether its Rock, Sand or any other. Switching back to Select mode does not re-correct the resolution issue, restarting the editor fixes it again, until you enter Landscape Mode. and within seconds it lowers the resolution, with a noticeable fan speed tone which then comes back down a bit.

So not sure what could be causing this, but again it makes it difficult to now paint, or add any detail painting since I cannot see properly on what details are being applied where, due to the resolution dropping down to a blur.

Please help let me know what I can do to solve this thanks.
Regards David.