Hi, subver, we got your email. It seems weird. Maybe you could try to fomat that sd card in x5, then replug it back to test. If the issue persists, i guess it is your new sd card issue as you said the your old 64gb sd card works perfectly.

Hi, yes, the 2.0 version cancels the otg function to keep the system stable.

Hi, PanzerIV, in this case, i think the x5 is faulty. Pls send  email to our support team(support@fiio.net). They will help to solve this issue.

Hi, sizetwo, is the screen on or locked when you press the volume button to change the volume. If the screen is on, the operation to choose next song won't be valid until the icon indicator of the volume on the screen disappears.

I have the similar issue. I refresh my x1 to fw1.6 version and it works great now. You could try to refresh it.

Hi, Ulysea, is the Mini usb cable broken? How did you use it with the tablet, via the audio jack? It is suggested to try another usb cable or usb jack in you pc.

Thanks for the response, rajibranjan. Yes, it is a bug and we will fix it in the official version.

Hi, Scottyj11 It seems weird as the usb mode works well. Would you pls uninstall the x5 dac driver, then disable driver signatures? BTW, it will be great to change another pc to test if possible.

Hi, i am a member of FiiO. This is just for old x3. The new firmware for x3ii will be released soon. 

Hi, Remixit, i got it in this link:http://www.aliexpress.com/store/product/Free-Shipping-FiiO-X1-Sports-armband-case/1473108_32270682259.html