As other's have stated DiPT is the obvious choice as it's known for auditory distortions. High dose disassociatives will often cause auditory pareidolia, or the tendency to perceive sound patterns in random noise. With the disassociatives a source of random "white" noise is what you're listening for. A fan, washing machine, or air conditioner can sound like helicopters, chainsaws, etc., and with a psychedelic thrown in you might hear music. Actual music or speech turned down very low or physically muffled in the presence of white noise is another good way to maximize the inherent capacity of a drug to create auditory hallucinations. You want to give your mind either chaos like white noise or distorted order at the threshold of perception like muffled music to maximize the amount of guessing you're brain has to do to make sense of it. Mixing aural processing confusion with drug induced signal augmentation and distortion is my recipe for auditory hallucinations.