You’re a Lieutenant in the Task Force 141, and you have direct permission, and orders from general shepherd and Captain Price to listen to music while conducting a mission because you work better under those conditions. They enforce it. The music is only cut off when someone is talking to you over comms, and the music selection is chosen by the one overseeing the mission, usually Price or Laswell.

A new girl had joined the task force and was a real bitch. So now she’s walking beside Ghost as he lead him, soap and Gaz into the building as she sticks to him with glue. Her talking is annoying him endlessly.

This time it was Soap choosing your songs because Price is beside you apart the mission, and Laswell is busy.