Thank you for allowing me to assist you, my name is Joe and I will be happy to assist you with your concern today.
If this happens even when it is sitting still then check mounting of the ducer esp if transom mounting, if in-hull mounted please let me know as that may be the problem. Make sure two ducers if equipped are not too close to each other (try turning one off to test in that case) Check wiring connections, check anything in the way of the ducer, if new ducer make sure plastic is not still on it, make sure it is the correct model ducer for the unit, pretty much eliminating everything but the ducer and unit itself. Also go in and instead of auto depth set the actual depth plus some extra feet and see if that works.
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