I just thought I'd add a quick topic regarding the USB audio input and the size of storage I've had success with...

When I bought the motor the dealer wasn't sure of the size limit of the USB that the audio system could accommodate, but said they knew 8GB was fine...

I started with that and bought a super small form factor thumb drive from Lexar (amazing this... It's barely bigger than my thumbnail).

http://au.lexar.com/products/lexar-echo-zx?category=1718

But my girlfriend has been complaining that her music is missing however, so I thought I'd give the 16GB version a go and can advise that that size is fine also.

Not sure what sizes others are successfully using?

I can highly recommend these particular drives and the small form factor means you're never going to jar it when it's fitted when rooting around.

Cheers MY15.5 Fuji White, SDV8 HSE Dyn Stealth Pack
Gone: MY14 Fuji White, 3.0 TDV6 SE
Gone: MY10 Stornoway Grey, 3.0 TDV6

Only using a 4Gb stick at the moment, however I noticed some of the tracks were not being recognised. A quick look showed that the tracks recognised were MP3 whereas the unrecognised tracks were straight from iTunes as MP4a files.
A quick conversion to MP3 made all the tracks available.

ITunes can convert tracks to MP3, or you can convert the tracks on the stick online at http://media.io/

I have been running a micro 16gb usb drive for years in the 2011 and 2013 - no issues to date Mike

2014 Facelift Discovery