Reply to Traktor not recognizing a pair of Akai LPD8's

I have had a single LPD8 for a while now and have not had a single problem with them. Ever since I hooked the second one up thou, every time I start up traktor I have to go into the settings and reassign each one a in port and out port under the controller mappings. Has anyone had a similar problem or better yet know some kind of fix. It's a minor problem and totally livable with but if it can be fixed it would be nice.