Need help troubleshooting my system

[schapman68]

I have a slimline dish and a HR20 box. I'm getting pixel drop on a few channels. The picture comes in fine on all channels but a few have this problem. Last night it was HDnet, Discovery HD and HBOHD. this happens about every 30 to 60 second part of the picture and sound drop

Sat info:
101=97%
110=93%
119=97
99s=NA
103s=na
103c=95