6K Pro External battery problem

Ok, love the camera, but I'm encountering a problem that maybe someone can test for me? I purchased a Tilta NP-F Battery Adapter plate and 12v DC plug. I put an NP-F970 on it (actual Sony battery) I wanted to see how long it would record off the F970 alone with no battery in the camera. It showed 11.3 volts for a little while on the screen, hit record to a 2TB Samsung T7 drive, went for about 26 minutes started to turn RED and just shut off. That was a new Sony Battery. Tried another new Battery (Sony) same problem. tried a 3rd one (I have a ton of these laying around for my Ninja) Same problem. I decided to try it with the supplied Black Magic battery thinking maybe it needed to be in there (the manual says it doesn't, but oh well) Same problem. When it starts to go RED I remove the Sony and reinsert it, it jumps to 10.7 volts for a short time and then goes to RED again. I bought a SmallRig NP-F Battery Adapter thinking maybe it was my adapter. Same problem, different Adapter and different cord. I checked my NP-F970 batteries and they were all 3 dead from using on the camera. So can anyone with a 6k pro test out yours with an external battery?

Cheers!
Mike

I believe that 12V up conversion is very inefficient. Did you try to use a dummy battery and 7.4V output on the plate instead?

sort of, I put a battery in the camera and tried the 12V and 7.4 volt connections. It powers up without the battery in and runs for 20 minutes recording and then goes black from battery going dead, its a 970 so it should last longer than the 570 inside the camera I imagine