DSM250 intermitent malfunction

[Ken Tait]

Hello again.
The set up is: RL80C Plus hsb2 W/GPS, DSM250, E66033(B260) Transducer & 4 ft open array.
I am having intermittent problems with the sounder. One day it works perfectly, the next it only works 50% of the time and another day it may not work at all. No reason I can make out. (time on, temperature, the radar operational or not, etc.)
When it works all is as it should be. Green LED flashes off/on and all the sounder options work fine.
When it does not work the LED status is: Red solid for 5 sec., Off for 1.5 sec., Amber 2 sec. Then Immediately to Red (no off between amber/red)—the sequence then repeats itself. Every once and a while, but not consistently it ads 2 amber blinks.
If I turn the power to the DSM off and then on again, it blinks amber, then green, (the sounder info appears on the RL80C screen) then goes to red and the above sequence starts all over again.
Anecdotally: When the sounder is not working, the RL80C shuts down and re-boots very every once in a while, but not often. It does this with the Sounder powered On or Off. I do not recall this happening if the sounder is functioning OK.
From what I gather from the manual the solid red sequence is a “fatal error” and the unit is power cycling. The every once and a while 2 amber blinks is loss of hsb.
Any idea what the problem is? Is it the DSM or the RL80C Plus?
Thanks for any help
Ken

Update: While you guys have been changing forums I did some additional tests. The unit worked for a few days so I had to wait until it faulted again. When it did:
I swapped out with another RL80C plus unit - Still faulted
I swapped out with another transducer (E66033) - Still faulted
BUT when I hooked back up original RL80C plus & transducer, unit started working OK.
Just checked it again, a day later and it is still working fine.

Any ideas?

Ken