I have installed three R7 units, all in the 5 slot. I had one bad port, and here I thought I must have somehow screwed up and let the smoke out of that port myself. I had dial tone on the pair as well. The replacement was out the next day on site, I swung by and installed it.
As a rule we try to do project management up front, and program in the office, or home. Then slap it on the wall, and cut it over on install day. Testing the ports in house with enough time to get an advamce replacement before the install if issues are found. It works well, the customer likes it, the cut is quick and install efficient when it is pre-programmed. We return one time within 30 days for changes included in the install price. We do not do changes on install day which are not mission critical, and the customer signs off on the project management info, before we go out. I hope I do not run into this issue again, but if I do, I hope it is in house not on site.