Brandt cooktop control knobs are hard to turn, loose, or do not stop at correct positions.

Safety first: For gas valves, turn off gas supply before removing knobs or front panels.

Steps:

• Remove knobs: Pull off the knobs and clean the area around the shafts with mild detergent.
• Inspect knobs: Replace any cracked or stripped knobs.
• Gas valves: If a valve is stiff or does not click properly, it may need lubrication or replacement by a gas technician. Do not apply random lubricants; use only approved products.
• Electric switches: If the shaft of an infinite switch is broken, replace the switch.