AT&T u-verse VoIP phone line

Need help. Have called several times about this issue and getting nowhere. When receiving calls on my home phone it frys (loud static) It doesn't happen all the time it happens often enough to be concerned. The static is so loud I have to end the phone call and call the person back. Once I do that the static is gone. When calling customer service, the support agent runs a series of tests and everything comes back normal. A technician has been out to my home and has indicated everything is normal. Keep in mind when running these tests, the phone is not malfunctioning.

I don't know what else to do. When tests are being ran none of these issues are happening