how to mark VOIP package
Here are a few resources to get you started on prioritising VOIP traffic on your router/network:
(1)VoIP Problems and How to Correct Them:
Video: https://www.youtube.com/watch?v=mnX6Im8GlJw
Presentation: https://mum.mikrotik.com//presentations/US16/presentation_3004_1462512668.pdf
Source: https://mum.mikrotik.com/2016/US/agenda/ID#0DMDMzO0A9
(2) Using RouterOS to QoS your network:
http://forum.mikrotik.com/t/using-routeros-to-qos-your-network-2020-edition/66683/136
You may also consider hirring a Mikrotik consultant to sort it out quickly.
I don’t know of a reliable consultant I can turn to.
A crude but effective method since its your own PBX:
On the Mikrotik that is Queueing traffic:
You can create a simple queue for all customer to PBX traffic and place it at the top of the simple queue list. PBX traffic will match this queue and all other will not and it will hit their normal queue lower down the list.
/queue simple add dst=PBX-IP-or-Subnet max-limit=200M/200M name=PBX-Traffic target=Customer-Subnet
Adjust the max limit to account for the combined total concurrent VoIP traffic of all your customers.