Are you talking coil battery or controller battery?
If it is the controller battery, the constant audio of non-motion pinooint mode combined with the fact that you are using wired headphones all the time might be the issue.
Having to use the internal audio circuit of the controller would tend to use more battery power. The wireless radio in the controller is on all the time to communicate with the coil so adding the wireless headphones does not appreciably increase controller power drain because the wireless headphone battery does all the work generating the power hungry audio signal. But if the controller has to send energy to drive it's own speaker or external wired phones, that might be causing it to drain faster. Just a theory. I could be wrong as I have never done a test to see if wired phones would drain the battery faster. You are the only Deus user I know who uses tfe FX2 phones regularly other than as backup to the wireless phones so not a lot of real world data out there on whether FX2 or speaker audio woud cause higher controller battery drain.
One of the reasons I got Deus in the first place four plus years ago is the convenience of wireless audio and now I use it exclusevely on all my detectors. Can't imagine going back to wired at this point, but I digress...
If it is the coil battery you are talking about, I am not sure pinpoint mode would affect coil power drain at all unless you had it on continuously. There is no documentation as to whether it requires higher coil power vs. the normal search modes even at TX power 3. TX power 3 is known to drain the coil faster (as you know), but not the controller. It isn't affected by TX3 or Pinpoint mode (unless possibly if it has to generate the audio as I discussed above). Though, unless you are running pinpoint all the time, I would think the search mode at TX2 you normally use would dominate overall coil battery drain, even if pinpoint mode does draw more coil power.
Then again, it could be a bum controller/coil battery. Possible, but unlikely if you have a new vice used unit.
Interesting observation. - I never thought about whether pinpoint mode draws a lot of coil battery power. I also rarely use pinpoint mode because I use pitch audio almost exclusively, which has the dual benefit of acting like a poor man's pinpoint mode, as I just position the coil to get the strongest pitch signal. Otherwise , if using tone ID, I just wiggle the target off the toe of the coil to pinpoint as it is faster than punching buttons to get in and out of pinpoint mode. I wonder if pitch mode would drain the controller battery faster if I was using the speaker or wired phones. Hmm...
Just some of my crazy thoughts and possibilities.
