At a loss (poor reception)

I have a trunk through metal NMO mount on my car. I have a multi band Larson antenna. I'm connecting to a 396XT. I have tried several different antennas but no matter what I do my receive on all bands is poor. I have tested continuity with my meter. I am currently able to pull in signals better with the stock rubber duck.

I'm not sure what I'm missing . Thanks in advance

At a loss (poor reception)