I did the same thing last year... I only hunted one day last year during the rut - that deer is still being eaten off of out of the cooler. So if one day of hunting will produce one good buck (or doe), then more fishing time on the water! Not to mention there's no boat traffic much during the...
The newer humminbirds with the Switchfire are unreal.. I've got a 788ci that blows my Lowrance HDS-5x out of the water... both have their particular features, but I won't stray from Humminbird again - not after the same types of problems you have and the customer service flat out sucks