I was poking around various musical instruments, thinking about how they would be in relation to the bard class, when I came upon the Aeolian Harp (or Wind Harp). Looking at it, it raises a couple of questions.
1a. Is is viable for use with Perform checks and by extension for use with Bardic Performance?
1b. If it isn't viable normally, should effects like Basic Aerokinesis allow it to be?
2. If it is, conditionally or otherwise, which Perform would it utilize? Perform (String) or Perform (Wind)?
The Aeolian Harp is such a passive instrument. As a GM, I would allow an aerokineticist or an air elemental type creature to create sound from the instrument by manufacturing and guiding the wind; to say that I would allow them to "play" the instrument with a given Perform skill, however, may be stretching verisimilitude to the breaking point. I could be persuaded to allow an air elemental type creature with incredibly fine manipulation of its body to move over the strings and produce music that is the product of deliberate artistic pattern rather than incidental sound, and in doing so would permit either Perform skill to work. I don't think Basic Aerokinesis would be a fine enough manipulation of the air to achieve a certain predictive mastery over the instrument.
I think a keener use for the Aeolian Harp is as a fixture, an instrument that can remain in place and produce a cantomantic effect when exposed to the wind, such as a semi-permanencied Calm Emotions effect, for example.