Do I need to pay for my On Hold music?

No. The music is Royalty Free. The sound files use composition from deceased composers whose works are now in the public domain such as Offenbach. The performers are typically regional orchestras who sell the right to use the music without limitation, they release it on a royalty-free software. Royalty Free means you have the right to use copyright material without the need to pay royalties or licensing fees for each use. You can use it as many times, for as many copies, to any volume, for any amount of time desired. This means for as many extensions you may have.

We acquired the music from a Royalty Free Software and have the rights to distribute as we wish.

In the past, allegations have been brought forward. However, they lacked merit because they were not brought from the original composer. Nor specifying which orchestra they represent. If you are approached with a claim please forward it to your account manager and it will be taken into consideration. Again though, without the Agent making the claim being able to specify the artist they represent, any claim will be considered frivolous and no more than a phishing scam.