All those were with my 93SV, same unit you have. Make SURE you put the ferrite core that came with your Garmin on the power line. I initially had the 93 running on the trolling motor battery and that was a disaster. HUGE amount of interference. I changed to the starting battery and the interference went away. But I'm running a small 20hp Suzuki. I'm not having any more problems now at all.
Tom