So what can we do to avoid inflicting further musical misery on our own customers while they’re patiently sitting on hold? We could just go back to playing a ringing sound, or an intermittent beep just to let people know they’re still connected, but that would be awfully dull. The best compromise is relatively simple electronic music that doesn't have too much going on as the ideal choice for hold music as it requires far less refined sound quality to get a decent rendition down a telephone connection.
“These big companies [and governments] are getting away with a lot,” Browder tells me. He hit a breaking point when frustrated with the process of appealing parking tickets. He built DoNotPay to cut through hassles designed to separate us from our money. In April it raised a $3.5 million seed round led by Felicis to develop an Android version after picking up early funding from Andreessen Horowitz. Surprisingly, the startup has never been sued.

However, if there is no other option but to place your customers on hold (perhaps during a busy season), you need to make the experience as pleasant as possible.
source: I have samsung galaxy y . i want to play music during call and callee can listen music. is there any app in android market? mikemangada Level 10 (Genius) Unfortunately there is no feature like this, If someone call you all media will be closed because how would you able to hear the person talking if the music is playing.