Bluetooth won't work on itouch

Hello, I have the latest update on the itouch (software ios4) and bluetooth had worked fine even after the upgrade. However in the last few days I have turned on the bluetooth, and it won't discover even the bluetooth headphones that I used to connect with. Does anyone else have this issue, and/or know how to resolve it, because it's odd that it will not not seem to discover any other bluetooth devices, it previously used to. Any help would be much appreciated.

PS There is absolutely no damage to the ipod because it has always been kept in a good case, and never dropped, so it definitely has no damage to make it stop working.