i have had picture and audio freezing all night tonight. every once in a while i get 711 on tuner 2. i have been watching 278, 265, 4 fox dfw and 11 cbs dfw. i check my signal strengths they are all in the high 80s and low 90s. i have an hr22/100 and hr21/100. slimline 3 SWM please help this is driving me nuts!!!