Ever since the upgrade to iOS 4 I have been unable to connect my iPhone to my relatively new Bose SoundLink wireless music system. This is months without use of a very expensive piece of hardware that simply connects through bluetooth. I would expect Apple to advance technology not take it away and yet with subsequent upgrades of the iOS over the original 4.0 it still is not working. Yet my iPad has no problem what-so-ever connecting.
I'm having similar issues as well. I just received my Bose SoundLink and was able to immediately connect my iPhone 4 (iOS 4.2.1) with the SoundLink. However, I was unable to ever get my iMac to sync with it using the USB stick even if I disabled the Bluetooth on my iPhone. When I "Forgot" the Bose device on my iPhone to see if I could get the iMac to sync (having the iMac being the only device that would have any sort of connection with the Bose) the iMac still didn't sync. Now my iPhone won't sync back either, the Bose system isn't even listed in the devices found. I've tried my iPad running the same OS version and it can't see it either. Calling Bose tomorrow!
Found solution on another forum: hold the remote's wireless key down CONTINUOUSLY whilst pairing any other devices. This isn't in the user manuals. Bose ought to rectify this in any firmare upgrade...