Originally Posted by wigwamclan
POWER DRAIN ISSUE.
Not sure if this has already been addressed but here goes,
I've got a Samsung Galaxy S4 running USB Audio Player Pro 1.0.9, OTG'd to a Fiio E17. The issue is the phone's power is being used really quickly whilst the E17 doesn't appear to be using any power at all....as if the phone is powering the E17!
Has anyone else had a similar experience? if so, is there a solution as at the moment it makes the setup I have is impractical as the phone is drained of power in approx. 2 hours : (
By default, OTG mode makes the phone (host) to provide power to connected peripherals (devices). Which means yes, the phone provides power to your FiiO E17. I don't own the FiiO, but check if there's a swich or something enabling and disabling USB charging on E17.
Please note that you will most likely still power the DAC cirquitry, while FiiO battery will feed the amp section. At least, that's how things are on my RSA Predator, which is also a battery-powered DAC/AMP.
Another solution COULD be (no warranties here...) is to make a custom OTG cable, with the power wire cut off. You can experient torturing stock OTG cables - they're dirt-cheap anyway. If FiiO can operate with no external power supplied to DAC - then it might work for you. If not - you can still use an external USB battery pack and custom Y-cables to provide data signal from the phone's OTG socket, while feeding power from the pack to FiiO.
Although, to me, it kind of edges on denying the whole purpose of portability...