Failing depth sounder ouput

[AngeloM]

I recently purchased a 2008 boat that was equipped with Raymarine equipment. And this is my first time on this board. i'm looking for some advice on a problem with the depth information displays. Currently the system general will display the depth up to 40 or so and then goes away on both the ST 60 display and the E120 MFD sonar display. The broker I purchased the boat from replaced the DSM 300 unit with a CP370 and stated that this should take care of it. While the replacement seems a bit more stable, it still loses the depth signal/data. The transducer on the boat is a B744v bronze thru-hull miltisensor.

I've reset the E120 to it's default settings and have reset the CP370, but no improvement.

Any suggestions on next steps to fix this issue?

Thanks,