AT&T Uverse poor reception

I signed up for Uverse internet and video service a few months ago. At first everything was perfect but they apparently have a problem with growth, performence contined to decline to a point where picture and sound quality is atrocious during prime time viewing hours. They have sent several repair people to the house to check everything but they have not solved the problem and the system is almost unusable during prime viewing hours. I am very frustrated at this point that they cannot solve this problem