I'm trying to help a buddy on his boat and he has two 997's on his boat. I would like to update both of them, is that possible from the humminbird site? Both units work decent but I'm sure if there's an update available it will help tremendously. I know both units are over 10 years old but can anything be done with them?

Also the interference issues are still on-going with the front unit. I've checked all connections (all clean & tight), all are run to the cranking battery and the power cord has been replaced. The trolling motor is a Minn Kota Maxxum (older as well), I'm just thinking there has to be a better picture available? When I had my boat when the 997 was new, I had a clean crisp picture (after an update). Could a older transducer be the cause? The cable is a little chewed up...

Just register them on the Humminbird website and if any support is still available, the current software will be put in the account.

Damaged cable, worn motor brushes, worn transducer, out of balance prop, bent prop shaft, and water intrusion in the motor are some of the things that will cause RFI where there was none before.