fan noise soundin weird

ok so im sitting here with the box door open and i got a fan on outside of the box pointing towards it.but my exhaust fan in the box sounds like it goes faster for a sec then lowers back down is this normal?

could be a surge on the circuit.. does it happen when ur ac kicks in?

dono it's in the garage,will this tho cause any negative side affects to my room?

should be fine infact your plants might really dig the strong exaust followed by the normal see what happens i dont see why it could be a problem