Hi , I was wondering if anyone has been experiencing issues with the multistream TPs on 5w?

I have a a Zgemma H7 running OpenViX 6.3.002 , and a 0.9m dish pointed at 5w , I have a SNR 91% / 15dB receive signal and most of the time have a steady picture on all the French and Italian channels using the multistream TPs!
In the last week or so I have been experiencing intermittent 'deep fades' where the signal will drop to ZERO for less than a second , but is enough to affect the picture and audio! Once the signal has recovered it can be anything from 2mins to 10mins before it happens again.

I have tried re-panning the dish and tweaking the LNB skew but cannot seem to get rid of the problem. We have had a mixture of weather ( clear skies to grey overcast ) which doesn't seem to have a bearing on the issue.

If anyone has had a similar experience and has managed to fix the issue , then any help of guidance would be greatly appreciated