E80 radar overlay blanked in close range

Hello all,
Powered up my E80 and noticed the radar overlay will not plot anything inside of about 1.75 miles. Any radar returns are being totally blanked out 360 deg around the vessel. I have:
reset the E80 settings, settings and data
reset the radar parameters using the auto feature.
I have manually tuned everything,
The Rx video is being blanked out.
Any control that has been adjusted makes a difference on something and appears to function. All the self tests related to the E80 and the Radar pass with no issues.
This happened to me (about 2 years ago) and I fiddled and fiddled and all of a sudden it was working.
Has anybody seen this??

Thanks

Phil