iTunes is able access two different media folders at once???

Hello,

Just in the last hour I discovered that my iTunes library is split across two locations and iTunes is playing content from both.

I normally keep my iTunes library on an external drive.

Today, I was transferring my AppleTV purchases to the iTunes library and when it was done I discovered it had put those files onto my internal drive - in the original music folder.

Obviously I had changed the location in Prefences (the when and the why are forgotten, but I must have).

However, iTunes is able to play the content on the external and internal without me needing to change the Prefences and my AppleTV can also access both locations.

I thought iTunes could only have one location.

Was I wrong?

Has this happened to anyone else?

Regards