Bad smell coming from Santa Fe stove

Hey all, this is my first time here and I'm hoping I'm not repeating a thread but I couldn't find one on my issue:

My Quadrafire Santa Fe freestanding stove is just over 3 years old. I've mostly been burning Golden Fire pellets especially this year. A week ago I noticed the glass and interior had become glazed with very hard dark ash that's difficult to scrape off. I cleaned everything as best as I could. I even took the brick wall out and cleaned behind and on the upper tubes.

Last night the stove started smelling like exhaust mixed with an slight electrical smell. The blower is now making a little noise as it works.

I am perplexed at what these two issue are caused by. The stove is cleaned regularly and I only use good pellets. If someone could help me figure out what the black glazing is and why I have an exhaust/electrical smell I would greatly appreciate it. Thanks

Thanks for the quick responses everyone. To answer Stevekng: wood exhaust. And to elaborate for tjnamtiw: Every year I clean the entire unit to included the exhaust piping. Since this winter in CA has been more like spring I have hardly been burning like I usually would. Thats why I was surprised to have to tear into it as much as I did as soon as I did. When I did clean behind the bricks this time there was minimal ash, since I had just done it a month ago.

I found the problem to be this: The black glazing I believe is creosote, thanks tjnamtiw. This was likely caused by the stove only running minimally and not getting up to full temperature partly due to the convection fan having some fuzz stuck in in. One side of the blower had sucked up a good amount of floor lint and I believe this was causing it to not suck enough air. After cleaning out the lint the blower noise I heard before was gone and the stove got much hotter. I then cranked it all the way up for several hours and let the creosote burn off. Everything seems to be working normal now.

Thanks again for the responses.

I've never had this problem before but I'm guessing its the warm weather. I typically fire the stove up in October/November and it doesn't shut off until April except for the daily cleaning. I don't know what the weather has been like over there but here we've been in the low 60's in the day and the 40's at night. We're actually in an official drought in my county.