Damper Setting? (Video inside)

[guitarjamman]

I have an Enviro EF-4 from 2000. The stove loves to pull air from a place I cannot track down. With the damper set at 1/2 way, the stove will blow out decent sized embers and has been known to flame out due to the dial-a-fire not being able to keep up. In the attached videos, I have the damper almost closed entirely (cracked open for just a little air). There is no black smoke visible while burning.

I do not have a mag. gauge, but based upon the videos - should I open the damper any further?

Thanks.