Card reader to use with tablet for walk-around sales?

We are trying to select a card reader to use with a Microsoft Surface tablet for walk-around membership sales in our lobby.  We purchased the MagTek BulleT KB model, but it doesn't input the card information into Tessitura properly.

Has anyone had any luck with a different model of card reader/swiper that will be compatible with Tessitura?  We need something small, that either connects via Bluetooth or USB - and small enough to either attach to a tablet, or for someone to clip on a lanyard, without being too clunky.