radios come with different receiver sensitivity and adjacent noise rejection... just part of the design. I can't recall who used to build honda radios or who builds them now... but in the late 80's and early 90's, their reception was some of the weakest I've known and auto-reverse mechanisms had a small ball bearing that was the achilles heel of the unit. They changed radically in the early-mid 90's and reception improved a lot.
Some areas do better with weak reception, especially in a crowded cit where busy airwaves can overwhelm a receiver.
stubby antennas, long antenna lines (rear roof mount), in-glass antennas, power antennas, all lose some signal when compared to a solid whip.
I can't fathom dealer techs understanding RF at that level or even having test equipment to discern equipment sensitivity / rejection.
See if they'll swap the radio... it could be a fault, or it could just be a weak design.