Why/how does switching devices "invalidate" the Bluetooth connection?

Question

Sorry if the title is confusing, couldn't really come up with a more descriptive one.

So I have a soundbar (Samsung HW-F450) with Bluetooth. I can and I do connect to it from my laptop to listen to music, which works as expected (=fine) the first time. If I disconnect from the soundbar and connect later on again it works even better because my OS remembers the device (for some reason named AirTrack) and I therefore can skip the "search for new devices".

But I ran into a confusing problem: if, at some point in the meantime, another device (laptop, smartphone) was connected to the soundbar the device-shortcut for the AirTrack that my OS saved for subsequent use gets invalidated and it cannot be used to connect to the AirTrack. The only solution then is to delete to device from the OS, search for it and re-connect this way. This even happens when connecting from the same laptop running different OSs (Ubuntu 14.04 and Windows 7, in my case).

I am aware that there probably is no solution to my little problem because thats just the cookie crumbles but I wondered if anyone could shed some light on this wierd machanic. It almost appears that the two devices (my laptop and the soundbar) maintain some sort of common state which gets "out of sync" when a different device has used the soundbar. Is my vague assumption semi-correct?