After going round and round with Avid support and getting past their usual "Herp derp please install the latest version of Pro Tools and learn to count to 10 and be able to tie your shoes" garbage they finally said to install a 2 year old version of Blackmagic Desktop Video for the i/o card and lo and behold that works. Video plays smooth in PT and the card still works for Resolve.
Sigh.... Avid...
Anyway, if anybody else runs into this issue, download the blackmagic desktop video version 10.9.6 which apparently is the newest ~tested~ version that works with PT. Here's a link so you don't have to hunt it down like I did:
http://esd.avid.com/ProductDownload.aspx?id=1722