I did my testing using an Archos 80 G9 tablet running Android ICS ( Ice Cream Sandwich ).
The 80G9 has a slot in the back of it with a removable cover. I removed the cover and plugged a USB extender into the tablet. I plugged a 8G USB memory stick into the extender cable. I had to go into *settings* and turn on the G3 option. While still in *settings* , I went to*Storage* and was able to determine that USB sticks are recognized when they are plugged in. I am not sure how to properly *unrecognize* a USB stick.
I tried using a USB hub as an intermediary... So far an Inland 7 port powered USB hub has not worked ( did not work in unpowered mode either ). Strangely , an unpowered 4 port hub from Inland seems to work.
Previously , I had loaded a 8G USB memory stick with music from iTunes. I activated the *Music* app installed on the tablet. I was able to browse thru the USB stick. It was listed as external storage. The music app successfully played the music located on the USB stick.
I am using a dual ended cable ( 3.5 mm stereo plug on each end ) . One end is plugged into the earphone output of the tablet. The other end has been plugged into various music players....... a Memorex Boom Box with a 3.5 mm AUX input ....... a stereo amplifier with a 3.5 mm AUX input.
Both amplified the sound cleanly.
Installing a USB Serial Port
I also tried using a USB to Serial Port adapter in the G3 USB slot.. I am trying the support offered by Prolific.
( Kudos to this site for providing useful information .... http://plugable.com/2013/02/26/prolific-launches-android-support-for-usb-serial-hx2303 )
This is the name that Prolific gives their package ==> PL2303 Android USB Host Solution
I was able to install the test app and it did show a connection with the USB to Serial cable. This only worked when I was using an OTG cable connected to the side of the Archos. I was unable to get the 3G USB slot to work. Although the app shows a connection... it does not run the loopback test sucessfully.
I am currently looking at the Java code that comprises the test app.
Here are some comments on driver problems .........
keywords: 777AndroidUSB Android ICS using USB memory stick to play music USB OTG