Little help with this DE=A1D voltage regulator
Assuming @IanS is correct about the part number (and the markings DE=A1D  on the datasheet do match perfectly), the "BP" bypass capacitor input is connected to something that is not appropriate. 

It is supposed to be a capacitor to GROUND of about 22nF. Leaving the pin floating will likely result in more noise (which may not even be noticeable in your application). 

The regulator is rated for 5.5V maximum input voltage so connecting it to 11V would likely be fatal, dissipation aside. 

Personally I would add the cap, then tap into the regulator output and measure the output voltage variation with input voltage variation. It should output 3.3V +/-2% for input voltage from 3.6V to 5V. If it's not doing that, replace the regulator (perhaps it is DEAD) or the whole module.