Rode USB Mic distorting

menamestom

I'm using a rode NT USB at the moment.  It's a good sounding handy mic for quick recordings.
But for anything but quiet sources it seems to distort.

It has an SPL rating of 110DB, so should be okay in front of a tweed deluxe at reasonable house volumes?

I've turned the windows gain right down and the channel in Cubase is low enough to prevent clipping, but it just can't seem to handle it.  Would you expect a 110db rating to manage guitars at reasonable volume a few feet away?

Perhaps it's time to move it on and get an interface again.  Trouble is for a reasonable interface and comparable mic it (albeit non usb) it will cost probably £300, but at least I can use other mics (I have Rode NT5's and a Rode M3).  The M3 is probably the same capsule anyway.