I had uploaded a wav file the correct size to my call settings.
It showed it was uploaded, verified, and now the same "keyboard stanard melody" (or whatever you'd like to term it) is still playing.
Called Comcast today and their solution was to call my voicemail, leave a voicemail and hold my phone to the computer while the music is playing as a voicemail.;..and then download that voicemail- THEN upload it as a file to the on-hold download prompt.
This is ridiculous. It sounds muffled and distant. There has to be a better solution. I was told by Comcast there was a "glitch" and this was the only way?