I had this issue this evening with a WAV file. Playback was twice as fast. Pitch was the same. Running Logic 10.4.7 on Mojave. Sample rates of project and file were the same.
Pulling in the file, the file blob would be the right length while loading, but when finally loaded, was half the length it should have been. I tried using the import function, dragging to a blank space in the track listing, and dragging into a blank Audio track. Nope.
I tried opening it in Audacity, where playback was fine, and then saving as a new file and dragging that in. Nope.
I tried doing the same thing in Logic, because--get this--in a brand new project, the file loaded properly and playback was perfect. Didn't work.
None of this worked.
That last part threw me, because it clearly wasn't ALL of Logic, just my one project for whatever reason. And nothing else in that project was effed up.
The only way I got it to function was to save the Logic project where it worked fine, and then import the Logic project itself into the original project. Then the file worked.
Just wanted to share in case this helped someone. But if anyone knows why this happened, I'd be happy to hear it.