747-400 Overspeed????

What is the normal crusing speed of the 747 and 737 series aircraft?
I've only just start to fly these big boys and I'm always getting the overspeed warning sign and clicking. The thing is I'm crusing at about 370 knots. It seems to me that, that is slow for these guys.
If it is slow is there a way to change the overspeed setting so the warning doesn't come on so quickly?
Thanks.
I've only just start to fly these big boys and I'm always getting the overspeed warning sign and clicking. The thing is I'm crusing at about 370 knots. It seems to me that, that is slow for these guys.
If it is slow is there a way to change the overspeed setting so the warning doesn't come on so quickly?
Thanks.