The best thing is to wait until he answers MJB's question. Without knowing what DAW he's using, it will be 3 pages of guessing.
If he's using REAPER, for example, it could have nothing to do with sample rate. It can be a simple case of having to change "Beats/Bars" to "Time", etc...(I might not be using the exact correct terms, but it's something like that.)
It has happened to me where I insert a track and it changes speed because of the setting I mentioned.