I have two units at the console. An hds 7 and elite 7 hdi. First problem.... My down imaging has bars going down the screen. Equally spaced. 2d has no interference.

Second problem..... If I try to run down imaging on the hdi and 2d on the hds I get a ton of interference on the hds. The hdi is only on down imaging.

You didn't say which unit has the down imaging interference, and what the other unit is doing at the time. You also didn't say if everything is fine when running each unit independently - changing nothing else.

The hds doesn't have down imaging only the hdi. The hds works perfect with on independent. The hdi still has the bars on the down imaging when it's on by itself

PM sent.

I haven't had any experience with the Elite units (yet, but do have to be installed on my small boat). I wonder if the Elite transmits both frequencies all the time, even if one image isn't called for display. This would explain the interference on the HDS, but I can't confirm my suspicion.