Got an email back:
Thank you for expressing your concerns and interest in DISH Network. Customer input is an important tool in our efforts to continuously improve the quality of the DISH Network service.
Your email helped us identify this issue and we were able to correct it this afternoon! Please let us know if you are still seeing the line (in live mode vs. any recordings you might have that contain this line) or if it reappears.
We appreciate the time DISH Network customers take to email their audio/video quality concerns. Thank you for your patience and for being a valued customer.
I haven't really checked the 722 but didn't see it on the 622. Can anybody else check to see if it's fixed?