Yes, you're partially correct...if you listen really carefully, the Audya's audio guitars played the chords alright, but they did not play the root notes (the descending bass line)..the guitars in the Yamaha played the bass line (using guitar only) properly.

In other words, when attempting to play a Cmaj7th/B, the Audya's audio guitar track was playing a Cmaj7th/C...when trying to play an Am7th/G, the Audya was actually playing a Am7th/A.

The Yamaha S910's guitar track was playing the proper root note for the chord the player played...a Cmaj7th/B came out as Cmajth/B....Am7th/G came out as Am7th/G.

I wouldn't like using the Audya's guitar tracks alone to begin a tune...you would need the bass track on, to give the descending bass line...with the Yamaha, I can do it with the guitar track alone.

A small detail? Yes. But, an important one.

Ian