Mike... With 2 4D's as a house bank, you have perhaps a 400 Amp Hour capacity. Usable capacity is 1/2 that since you NEVER want to go below 50% discharge. So..you have 200 amps at most to work with and you probably have more like 150 if your batteries have some age to them and have discharged regularly below 50% (12.25V at REST with no load for at least 1/2 hour).
In my experience the Adler Barbours draw about 6amps...so even runing 50% of the time... you should be using maybe 70 amps a day...leaving plenty for your TV and lighting needs which might add up to 25 or 30 amps. So....something is off here and I suspect the root cause is your charging system. With a battery bank of your size you should have an oversized alternator (say 100-120 amps output) backed by a 3 stage smart regulator that can properly top up your batteries. Stock engines usually come with a 40amp range alternator which will continually NOT fully charge your batteries and eventually cause them to lose capacity. I further suspect that your batteries are less than good at this point and may need to be equalized or replaced...but new batteries will fail if your don't get to the root of the problem.
If the batteries are flooded cells...a hydrometer can check the individual cells and you can get one at any auto store cheap. Make sure there is NO load on them for a while before testing.
I would also get yourself a LINK system to monitor what is going on with your house bank in both voltage and amp usage so you can understand your various loads and adjust your charging regimen.
I've made a LOT of assumptions here in an attempt to answer your question...so let me know if any of them are wrong as it might lead to a different conclusion! Good luck...