Perhaps it's the heat combined with sleeping in a covered crate. Is the crate large enough for him to stand up without having to keep his head down, to turn round easily and to lay down at full stretch? If not, he could probably do with a larger crate to help keep comfortable.
My two aren't crated, but have the hall, kitchen and study to sleep in. They are very good and always quiet but during this hot weather I hear a bit more movement than usual at night and it's because they are leaving their beds periodically to cool down by stretching out on the kitchen or hall floor, or going into the kitchen for a drink from the water bowl. Most of the time they don't seem to drink during the night, but at the moment they sometimes need to.
