With pc there will be no problem but I don't recommend it with defy+ because as per my knowledge amping increases noise if the inbuilt amp of your phone is not bypassed, yours' seems to be the same case. With windows you can use the wasapi plugin for amp bypassing.
*www.techpowerup.com/mobile/reviews/Head-Direct/FiiO/E3E5/1.html <---- refer this for more clearity
Amping would be useless for you mees