Question on Lopi 380-96 secondary baffle

My wife and I are new to wood stoves. We purchased a home (approx 1750 sq feet) with Lopi model 380-96 (prequal to the Endeavor) already professionally installed. This stove has been in the home for several years. Prior owners kept stove and Chimney in excellent condition. Chimney has been swept. There are no obstructions in the chimney. Damper located in the chimney as this model did not include a damper. When burning, the stove is more than adequate for heating our home. However, we noticed a strong smokey smell in the home. We then observed light amounts of smoke coming from underneath the heat plates on the sides of the stove. (NOTE this occurs after the fire had been burning for 2 days and chimney was well heated). Damper was approximately half closed. Upon inspection, I noticed there is a 1 half inch diameter hole on each side of the stove. After downloading the manual from Lopi, these holes appear to connect to each side of the secondary baffle which is inside the firebox. The baffle itself appears to be clear - none of the holes in the baffle are clogged.

I don't want my damper open 75% to 100% all the time due to lost efficiency. Is this a common issue with this model? If it is, we may be looking at getting another stove.

begreen, It's a metal chimney. I've inspected the exterior but don't see any cracks. As to the inside, I have not removed anything (fire bricks) to inspect.

blacktail, damper is in the chimney. The damper comes standard on later models, but did not come on this one.

Thanks for all of the feedback. Learned a lot with this post. I was mistakenly comparing a flue damper with a bypass damper. Also better understand secondary combustion. The flue damper is in the connector that goes to a stainless steel pipe. I'll leave the flue damper open.