The answer to 'junction box burning smell' is that a burning smell coming from an electrical junction box is a serious issue that requires immediate attention. This could be a sign of an electrical short, overloaded circuit, or other dangerous problem that needs to be addressed by a professional electrician.
Some common causes of a burning smell from a junction box include loose or corroded connections, damaged wiring, overheated components, or an overloaded circuit. Symptoms may include flickering lights, tripped circuit breakers, or visible signs of burning or melting inside the box. This is a fire hazard that should not be ignored.