"Very often" sounds like a lot more than I would say. I've been using Qwen 3.6 27b Q4 in Pi (with out any anti-looping extension) daily for weeks now, and I've had it get stuck in an infinite loop maybe 3 or 4 times.

You can fix looping with proper repetition penalties. Turn on the one called “DRY” that PeW invented and got merged into llama cpp