Comment by lstodd

No idea about bicycle, but for motorcycles, integrated helmet headphones are a thing for long time. It maybe helps that a typical motorcycle helmet is quite noise-cancelling by itself, so one relies mostly on moving faster than traffic and if that fails, on mirrors and not on sound.

Besides being an mc person I always considered bicycle helmets a useless compromise in that they don't provide true protection like full-face motorcycle helmets do. You're still as likely to leave half of your face on the obstacle, so either don't bother or wear something that would prevent that.