Considering that the as pie social stigma puts many of us at a disadvantage, I'd suggest aspies don't play at all and turn to composing and writing songs.
Personally, I've never been comfortable setting my own awful poetry to music, but I've always heard music in other people's poetry and song lyrics.
My special interest in music has in recent years turned to church music, and it was a sort of dream of mine to set Biblical passages to music, but I just didn't "hear" it. I've gone to a few Christian songwriter workshops with some of the top publishers in the business, and this summer I had one of those lightbulb moments: The artists I listen to the most aren't that original at all, and I find a new song every time I open the Bible. So I've started working my lyrical skills, and I'm hoping soon to rehearse one of my songs with the choir and get it in the usual rotation in our church.
Otherwise, I'm developing a small instrumental program which requires that I write arrangements for the instruments we have available. So while my station is at the piano, I'm also expressing myself through a flutist, violinist, organist, guitar, bass, and drums. I even record and email demos for my musicians to have something to practice with.
I'm not an alpha-dog leader type because it's so difficult to convince people to do what I want them to do. But it's interesting right now because there is a void in our church music leadership and nobody else can do what I do. So I think the hyper focus and attention to detail has put me at somewhat an advantage. For as long as it lasts, I'm going to enjoy being in charge.
The ultimate aspie instrument, the ultimate instrument, is the combination of ink and paper that express the composer/songwriter's intentions and induces groups of musicians to realize the composer's musical ideas.