Strange issue with changing Naza voltage level via iOSD

[globalwad]

When I take my freshly charged 4S lipo (16.8v) and plug in into my TBS Discovery, my DJI mini iOSD my reading shows 16.4v. If I then remove my battery and use it to power my buddy's exact same setup, his mini iOSD shows 16.8-16.9v using the same battery. I've tried multiple packs and its the same, my OSD show about .5 less using the same pack.
At first I had my NAZA PMUv2 soldered to one of my ESC/Board connections to get power, but in my troubleshooting I have moved it's power pickup over to a spare +/- on the board. But no change.
Anyone else seen this before? Is there something about my build that could possibly be eating .5 volts with no load? Thanks.

 

[kloner]

I've seen variances in iosd voltage readings. the best way would have been to use the core osd since it shows the current draw you would know if this is actually a problem or not. Another indicator would be if you feel heat any where. After that you can use a multimeter to check current draw and make sure nothing is shorting out.

 

[globalwad]

Appreciate the input on this. Turns out it was my poor understanding of the Naza voltage calibration setting in the Assistant Software. I wrongly assumed that when you plugged a fully charged battery in and then hit 'calibrate', that it would actually read the current voltage of said battery, but it doesn't. You still need to manually input that actual voltage of the battery you are 'calibrating'. So I took a fresh pack and entered 16.8v and hit calibrate and now it shows properly.
Strange.