Looks like time to hoick it up on a ramp and have a good look around for hot gearbox oil pipes, exhaust bits, and generally make sure nothing hot under the floor pan is in trouble. If you find something, job done.
You don't mention hot SMELLS, so chances are it isn't serious - yet, maybe.
Find a fellow TD5 Auto owner and check if his does the same.
If not, remove the centre console - not too serious.
My bet goes with hot air from the heating system, possibly a duct pipe off somewhere, if it isn't from under the floor-pan.
CharlesY