Need Advice. Picture problems.

This is not a new issue for me. This has been going on since I purchased the Roamio Plus about a year ago. A am a long time Tivo user. Love the product and services provided. I have a Fios connection. My RS uncorrected/corrected is a moving target. RS uncorrected=blocking. I can hit the sweet spot through trial and error and get the RS corrected to increment marginally. But it is a moving target and will get worse based and many variables including outside air temperature, moving the Tivo even the slightest bit, a reboot, and software updates (the latest). I can never get RS corrected zero. My signal is either to hot or to cold (according to Tivo tech support). Lately the fluctuations have been epic and this last software update (which I love) has made it impossible to get a clean signal (RS uncorrected 0). I have tried everything to fix the problem. The latest was bringing out the Fios tech. He verified the signal is clean at the Tivo outlet. He also replaced my ONT at my request. My latest connection is a direct connect of the coax from the Tivo to the FIOS ONT. No splitter at all (trouble shooting anything else being on the line causing the problems). I have 15 db worth of annuators at the Tivo outlet. A 3 db and a 12 db. This seems to get the signal where I need it. But I know it wont last. Tivo tech support wont deal with me unless the RS corrected and uncorrected are zero. I recently elevated the issue to a manager and he agreed to replace the Tivo if I wanted. The question is will it solve the problem? Any advice on this issue would be a appreciated.