It is real handy to pair my SX900 with my mobile phone. Audience members often ask for a good song that I don't play. A quick YouTube search and I can play it through the SX900 speakers or external speakers. Cool!
So, I'm on a job and suddenly my speakers start blaring out the ring tone on my phone startling the entire room. I was dumbfounded before I realized the pairing of my phone to the keyboard just made the keyboard an external speaker for my phone.
From now on, I will pair the SX with an iPad and hope nobody tries to Facetime me while I'm on a gig.