Ringtone stuck on iPhone

Hi,

I was syncing some ringtones on my iPhone 4S today and I've encountered a problem. I had one version of the ringtone synced, and then decided I wanted a different version. So I deleted the first version, placed the second version back in my library and synced again. Now no matter what I do, the first version is also stuck on my phone. I've tried unsyncing all ringtones, removing both versions of the ringtone, syncing select ringtones, resetting. No matter what, that one ringtone is on the phone, even though it is nowhere to be seen in my iTunes library or on my computer at all (even when I unsynced all ringtones, it remained as the lone ringtone left on my phone).

Does anyone have any idea how I can remove it? I have no idea why it is still there. It's no longer in my library, so it shouldn't be on my phone.

Thanks!

Dean