Basic regulation failure

[Aphonic]

Perhaps someone here can explwin to me why the dna75 chip doesnt do basic regulation like boosting. Or where there is a setting to turn in stabdard regulated mod behaviour. First a couple of notes to answer questions before they arise I have 16 18650 batteries. This behaviour is consistent on every battery. All bought in sets of 2 or 4. All healthy. All functioning perfectly in mech and regulated mods. Some are a week or two old. Some a month. some a year. Mostky 25r but some vtc5 (authentic) l. Various vendors. Most rewrapped by me after tearing (bad battery case caused issues wjth the wraps but no damage to the batteries) and confirmed authentic. the build specifics are irrelevant as it hapoens with any builds,1.2ohm. , .5, .8, etc but ill discuss whats on there now The same thig happens under sny orifile or material. In temo control or power mode m With a full battery i can boost basically as much as i want, the issue occurs bekow 50% The battery level is the same or better on other mods The remaining battery caoscity when the dna75 chip gives issues js still well within reasonabke operating levels - above 3.2 Im using the bets firnesre which stopped the karge battery low frok flashing but the same issue existed eith the stock firmware. The problem If i set the mod (smy sdna 75) to power mode and configure the device to 26w wih s build on top of .67 (4.2v) when the battery isnunder 50% the wattage set is not maintained - the battery icon flashes and otoit is reduced. The rediction ibviousky varies based on remaining battery life. The basic function of a regukated mod is to maintain a power kevel through thenusabke battery life. If a chip cant do that basic function its useless. If I wanted drop off i would use my mech mods. This isnt a safety issue. And total amp draw csn be as low as 3.5. So we arent hitting amp limits. I am a mtl vaper so its rare i use even the power bejng jsed bh the current build. When using a regulated mod i expect to get my set wattage until the battery is exhausted. Replicate Install atomizer and battery with

[Spector NS5 RD]

welcome to the forum Aphonic. a couple of facts to know about the dna 75 board is..... 
the max output voltage is 6.2 volts. so any build over .5X ohms and you will not get the full 75 watts.

if the battery is making a poor connection to the board this will trigger the weak battery message. this will also happen if your batteries can not supply the current the board demands at any set wattage. the max the board will draw is 28 continuous, 32 pulse, instantaneous.         here is the spec sheet 

https://downloads.evolvapor.com/dna75.pdf

i have the SMY SDNA 75 myself as well. i find i only get the weak battery message at around 3.1-3.2 volts (remaining battery voltage). this running it with a 75 watt preheat and 60-65 watts to maintain temp. i am using some good batteries for this mod, LG HD2C, they are perfect for the high current demand from the board when running at the dna 75's upper wattage limits.

post a screenshot of device monitor while firing the mod and make sure all of the battery/wattage options are ticked so we can see what the device is doing.  i suspect a lot of sag but post  it and lets take a look.

edit.......i should note, SMY SDNA 75 has one of the better battery sled contacts out there. they hold the batt pretty tight for a solid connection.  you could have a faulty unit (poor battery wiring soldering),this if you know for a fact your batteries are in a healthy condition and have a CDR that meets the dna 75's current requirements.

[VapingBad]

Hook it up to EScribe and select pack, current, voltage and power and vape, I suspect you will see that your cells are hitting one of the safety limits.  Probably the min voltage limit (pack) of 2.75 V, this could be a connection issue or just decreased performance with old cells.