The most common codecs are G729 (compressed) and G711 (non-compressed). They are designed to compress human speech, and often cause a loss of audio fidelity — which is worse in some languages than others. On hold music that has been specifically designed for that purpose, to be used with VoIP systems and codecs, can sound great. But it is not easy to come by.
We are known for having the EASIEST TO USE interface in the entire marketing industry and have literally hundreds of testimonies to support that claim. Custom written and recorded messages Pre-built libraries with thousand of messages for specific industries, like… Banking/Credit Union Medical Dental Veterinary And More Record your own messages with Record24™ You can even play your own radio spots Is Your Service Compatible With Our Phone System?

That’s a big piece of a trillion dollar pie! The good news is, you don’t have to let all these callers off the hook. Studies show that with creative, professional sounding on hold messages your business will retain customers holding on the line (in fact callers will wait up to 3 times longer than silence or music), but you can also generate revenue by marketing additional products and services.
If it is a genre, hold music, it's fair to say, is a troubled one with few hits. It's not really meant to be loved or even listened to — it's meant to communicate something specific: Don't hang up. (Cornell makes this plea specifically at the end of his song.) Silence is believed to be a death knell for phone calls — people will simply think the line is dead and hang up. This is true even on non-hold calls; it's why phone companies transmit something called a "comfort tone" over phone lines, a barely audible synthetic noise that signals a connection is still there.