Were caused by physical noise. Noise is a factor that affects communication. The noise has been divided into 4 forms, depending on its origin: Physical, physiological, psychological and semantic noise.
Physical noise is that caused by factors external to the listener, for example, the noise of cars.
Physiological noise is produced by internal problems of the speaker, for example, rapid speech.
Psychological noise is an interference within the speaker's mind.
Semantic noise occurs when the speaker and the listener have different language systems.
I hope my answer can help you.