Loop strechtes automatically

Hey Cubasers,
I have this issue since long and i really don’t know what to do! It is not happening with every loop i use. Only sometimes. When i drag a loop into Cubase 4, let’s say 127 bpm, it became faster than it actually is!! I set the project to 127 and every other loop fits perfectly between the left and the right locator except some loops, they become faster and the loop block becomes smaller than the area between the left and the right locator. If i play them outside cubase they are normal but when i drag them into Cubase they become faster. I hope i am clear enough and thanks in advance for help.
M

check the samplerate of the loop is the same as the project.
Also is musical mode switched on?