Motorised satellite allignment and signal problems

Got a vu solo2 with openatv 6.2 and had no problems until recently.Set up with usals and the co ordinates are correct but getting severe break up on most satellites astra 28.2 east probably being the worst!Funnily enough hispasat the best.Getting snr99% db 17,0 on hispasat. When i move to Astra at 28.2 getting snr 99% and then goes tosnr 0% dnb 0.0 .! The dish looks fine as does the lnb any help would be appreciated thanks

Thanks a lot lot for the reply water ingress could be the answer problem developed after the heavy snow we had.