Some people are talking that the new verison of mIRC would be able to play music on a channel and everyone's at the channel would listen...
I would like to know if this is true and the news about the next version!

Khaled and his team never discuss new features which will be (or might be) included in the next release of mIRC. We are never prewarned when the new mIRC will come out either.

All you can do is go to the Feature Suggestions forum and post there - All you must have heard is a fake rumour.

Regards,

If you would like to understand how to play a sound for others to hear, in any mIRC window, type /help /sound and to play a sound that only you hear, type /help /splay

Of course, only ppl who have the sound will be able to hear it.