Diagnosis
Not defective, that's just how these pellet grills work. The 'Smoke' setting runs at a very low temp with a slow pellet feed for maximum smoke, but it often struggles to produce a clean, thin blue smoke. You might be getting thick white smoke, which tastes bitter.
How to Fix It
Try using a 'smoke tube'. It's a metal tube you fill with pellets, light one end, and place in the grill. It smolders independently of the controller and produces consistent smoke for hours, even at higher cooking temps. It's the universal hack for pellet grill owners wanting more smoke.
If That Didn't Work
Your pellets might be the issue. Old, damp, or low-quality pellets produce less smoke and less heat. Always use 100% hardwood pellets (no filler oils) and keep them sealed in a dry place.
Heads Up
Chasing heavy smoke on a pellet grill often leads to 'dirty' combustion and soot on your food. The trade-off for set-and-forget temperature control is a lighter smoke profile. It's a design thing, not a you thing.