a few quirks of the new rig Springdale 294BHSSRWE

yes, that jensen does have a noticeable drain. Even in the "off" position, it is really in "standby" drawing current. So... either you need to install a battery disconnect or disconnect the batteries when stored. And if you dry camp much, install a switch on the standby power to the Jensen.

IMHO put good disconnect switch (perko, blue sea etc.) on the main line from the battery to the trailer. either on the tongue or in the pass through. I installed mine in the front pass through compartment.