bit of a weird on but i will ask anyway

[deejaypeejay]

i have a zone 2 dish up for astra/eurobird 28.2E every now and again little green squares will flash up on the tv for about a millisecond but enough to see them. what are they? the picture does not break up or anything it just happens every now and again. my dish is perfectly aligned i have 96% strength and signal quality dropping to about 86% in heavy snow/really heavy rain. i get these squares mostly on chavland tv err i mean clubland tv when the wife watches it and flava

just intrigued to know

thanks