Problem with Simple Voice Chat mod (Forge)

So recently me and my friend we were trying the Simple voice chat mod and i invited him to the server using the regular aternos ip like SilentCharizard.aternos.me, but when he joined he complained that it said Voice Chat unavailable so i got confused but when i gave him the Dyn ip it worked so this made a question in my mind that if i need to tell them the dyn ip every single time because it had the servers port like 2444 or is there like a way of doing this like SilentCharizard.aternos.me:2444 if yes then please tell me because then i would need to tell them the dyn ip everytime so they can join?. Iam gonna be using Simple voice mod on exarton so i really need to know because on exarton they can wake up the server whenever they want and if we have to use dyn ip we cant talk unless the server owner (which will be me) will have to give them the Dyn ip. And by the way iam asking this because it wont just be me and one other friend it will be like 5 or 6 more friends and it could become very bad for me.