Hi Fatboylow,
Thank you for posting in the Apple Support Communities. It sounds like you're trying to play your music from iTunes with a paired Bluetooth device, correct? If so, we'll do everything we can to help. We've done some research and checked to how other Windows users were able to resolve the issue, and it sounds like the below steps will take care of the issue.
You need to change your audio playback source in your iTunes Preferences menu.
Go to Preferences > Playback, then select "Direct Sound".
Close the iTunes app, and reopen it.
iTunes should then use the paired BT speaker directly.
Please let us know if you have any additional questions, or if this doesn't resolve the issue for you. We're always happy to help.
Cheers!