I had the same problem. It helps to have the HDS head unit close to the transducer., especially in shallow water. I installed the LCG4000 external antenna and now I have no problem finding stuff. However, I still trust my Garmin more. I really got the LCG4000 for slow trolling accuracy and direction below .5mph. LCG4000 makes a difference for me. I actually went out with billbob the other day without my Garmin. No problem, but I wasn't overrun with confidence without the Garmin either.

Also, best to zoom in max. At present, my HDS7 will only zoom in 50 feet, but I only have base maps on it. Not happy with this crap zoom restriction at all.