I didn't ask that. What are the OFFSETS you put in to reach 75db?
Also how long is the cable you are using?
What type of cable are you using?
None of the 3 above questions are relevent to MRC. I use a cheap 30' Belden RG-6 coax cable with cheap RCA F-Conn terminations.
The more significant question would be is it 75ohm.
Pure and simple...MRC has problems. M needs to step up and address all the issues. It should work the 1st, 2nd, and each subsequent time without a problem -- no matter who's running it and their level of experience.