[Galaxy Note 8.0 (Tablet) Q&A, Help & Troubleshooti] bbfoto:
Wait...So are you getting video only, and no audio, or nothing at all???

Did you check the Android settings under "Accessories" for audio output options when docked or when other accessories are attached?

BTW, are you using the ARliberator App?

First of all, I don't think that the Note 8.0 is on Pioneer's list of approved/confirmed devices for use on the AppRadio2. ;)

Also, the MHL/HDMI adapter that is sold in Pioneer's "Android Connection Kit" is the older 5-pin micro-USB connector.

You tried it with Samsung's newer 11-pin microUSB/MHL-to-HDMI adapter that is made for the SGS3 and Note2, right??? And you are plugging in the adapter to a microUSB charger, right? It will not work without this.

Pioneer's and Samsung's adapter for the SGS2 and original Note 5.3" will not work because it is the older 5-pin microUSB/MHL connector. You can buy the Samsung 5-pin to 11-pin MHL adapter for about $10 that should allow the older MHL/HDMI adapter to work:

http://www.amazon.com/Original-Samsung-Adapter-Converter-EPL-FU10BEBSTD/dp/B0083FYL0O/ref=sr_1_6?s=electronics&ie=UTF8&qid=1366945559&sr=1-6&keywords=samsung+5-pin+to+11-pin+mhl+adapter

I don't know why you'd want to use the smaller and lower Res AppRadio2's screen over the Note 8.0's anyway?!? I guess you lose AM/FM tuner and the Backup Camera if you have one.

You can bypass the AppRadio2 and just use your Tablet to get RCA line level preouts and Digital Optical (Toslink) audio from the Note 8.0 if you use the MHL adapter with this $40 device:

http://www.amazon.com/ViewHD-Premium-Audio-Extractor-Converter/dp/B00AHS8LD8/ref=sr_1_1?ie=UTF8&qid=1366941077&sr=8-1&keywords=viewhd+hdmi+digital+audio

Oh, but I forgot to mention that you would need separate car audio amplifiers to power your speakers for this setup to work. :/

I just returned my AppRadio2 and am using my SGN2 with this adapter in my car audio system to get digital audio output sent from my Note 2 to the digital optical input of my RF 3Sixty.3 DSP, then to my amplifiers and then speakers.

I'm using my Note 2 because I wanted to use just one audio source/device, that also has cell phone capability. The AppRadio2's built-in Dialer/Phone app borked/hid my Note 2's Keypad when it forces the display into landscape mode. :/ I guess that I could have used Tasker to switch back to portrait when the dialer/phone app opened, but then it is tiny on the AppRadio2's display. The International GT-N7100 SGN2 also has a hardware FM Tuner, or I use TuneIn Radio to stream almost any AM/FM station worldwide.

My car also came with a handsfree Bluetooth setup that worked much better than the AppRadio2.

I'm also using the Samsung SGS2 SmartDock in combination with the USB JoyCon EXR plugged into the SmartDock to keep my OEM Steering Wheel Controls and add extra functions to my SWC by long-pressing the buttons, etc. You have to program the JoyCon EXR with your PC before installing it, but it works great to control your Android's audio player functions with your SWC.

If you do get it working, you'll probably want to use the "Screen Standby #root" app to turn off the Note 8.0's screen backlight without putting it to sleep so it charges up faster. You must be rooted to use this app, however.