My First though on this wound be to look for anything that is different on the bottom, if you know the fish are staying in the part of the lake you are fishing in. I would look for the deepest water and then look around to see where they are going to feed at. Crappie will be in cooler water and run up to shallow water to feed on minnows and bugs then go back to there holding place. If you find a deep pocket with stumps close by try to set up between them and throw a jig around the stumps, if they are not there throw to the deep pockets. If you have no luck catching them then try a deep pocket with something different then stumps, like the lily pads.
With water so shallow you could be spooking the fish before you get to them. You didn't say how you are fishing but I would try putting 16' rods out in front of the boat and slowly troll around with the jigs about 30'' deep. That way it give you 16' before your boat has a chance to spook the fish. When I say slow troll, just tap the trolling motor when the boat stop's moving. Try to keep you lines straight up and down, if the bites are coming after you tap the motor the fish are telling you to speed up a little, the fish will let you know how fast to fish just pay attention to when the bite comes.
Sometimes tipping the jig with a minnow will help. Maybe this will give you something different to try. Good luck with your fishing.
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