Getting Google Now ("OK Google") to work with a USB DAC: If you are in FI mode and you are using Behringer UCA202 as the DAC (which works great, btw, with the Nexus 7 - I highly recommend), then you will need to connect an external microphone for any voice commands to work, such as for Google Now ("OK Google") or AutoVoice. The UCA202 has two input RCA jacks but you cannot connect a mic directly to those jacks because the output signal from the mic is too low. You will need to run your external mic through a preamp to bring the signal up to line level and then into the input jacks on the UCA202. Then it works just fine. At this time, Amazon sells a very small mic with a built-in preamp for only $7 called, "VideoSecu High Sensitive Audio Pickup Device External Amplified Tiny Spy Microphone for CCTV Security Camera." Catchy name, eh? It works great with the UCA202. There are two lines coming from the mic that you have to connect. You connect the red line to a 12V power source (I had to do some creative wiring because the plug that comes with the mic is made for a security camera.). Then connect the white line from the mic to either of your input jacks on the UCA202 - either jack will do, you don't need to use both of the input jacks if the mic is only for inputting voice commands. That's it. The mic is very sensitive for picking up your voice over car/road noise and is so small that it's easily hidden on your dash. Hope this helps.

Here's a link to the mic on Amazon: http://www.amazon.com/VideoSecu-Sensitive-External-Amplified-Microphone/dp/B0053V5Z9W/ref=sr_1_1?ie=UTF8&qid=1426107388&sr=8-1&keywords=VideoSecu+High+Sensitive+Audio+Pickup+Device+External+Amplified+Tiny+Spy+Microphone+for+CCTV+Security+Camera+with+Bonus+Warning+Decal+WD6 And of course the link to the DAC: http://www.amazon.com/Behringer-UCA202-Audio-Interface/dp/B000KW2YEI/ref=sr_1_1?ie=UTF8&qid=1426109117&sr=8-1&keywords=uca202

And the OTG cable you'll need to connect the DAC to the Nexus 7 and power source: http://www.amazon.com/gp/product/B00EB70PXA/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1