Dial cmd Options m()

Hello everyone,
I use asterisk for a while. But for this problem I did not offer a solution.
So I chose to raise it in this forum maybe there is something I missed.
I have to write a dialplan that transfer a call like followme and Provide Music on Hold to the calling party until the called channel answers.
See below :

exten => 1000,1,Answer() exten => 1000,n,Dial(SIP/4029,15,m(wait))
So far so good.
I wish that instead of using [color=#BF0000]m(Music on Hold class)[/color] to use the “file name” of sound file directly.

I will explain again not to use the “Music on Hold” instead use file name so we can replace the file of Hold to the calling party until the called channel answers dynamically
Thanks
woren