Missing Option 24/82 and intermittent overpowered signal

For the last 14 years I've suffered from internet dropouts. Sometimes once a month, sometimes 20 times a day. Eventually I found that the Internet wasn't dropping out, my entire modem was rebooting. The first modem I ever had was a comcast modem. I had it replaced hoping it was just faulty hardware. A few days later the issue persisted. After a few months I decided to buy my own modem, a Motorola whose model I've long forgotten. Again it seemed to help but a few weeks later the problem again returned. I called techs many times in the years following. I've had every run of cable replaced 4 times over. I've had signal boosters and signal dampeners. I've moved the modem to different rooms, I bought a very pricey gigabit modem from Motorola and high end router from Asus, which did nothing. I now have the new xFi Gateway, which, of course, has fixed nothing.

Looking at the modem logs of my previous modems I saw T3/T4 timeouts flooding the event logs. In my new xFi gateway it's Missing option 24/82. The same rebooting, the same intermittency. I've gone weeks without a problem on occasion. Other times I'll experience up to 3 dropouts an hour for days. Most of the time its about 3 dropouts a day, with one or two back to back dropouts thrown in for fun. Rebooting doesn't help, unplugging the gateway for 30 seconds doesn't help, unplugging the lines doesn't help, factory resetting doesn't help. There is no discernable pattern as to when the issue pops up. Rain or shine, hot or cold, day or night, windy or not, winter or summer. Number of active devices on the network doesn't seem to affect anything either. The only clue I have is that I noticed a few years ago that my signal strengths weren't quite what they were supposed to be. Recently a tech came out and told me the power levels in the line were too high. He added a dampener to the line but it didn't seem to make a difference. 

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