How to improve VOIP communication through the Mikrotik setting with an LTE connection?

Question

VoIP

Mikrotik 951 distributes the Internet from an LTE modem. The key feature is speed, it can be from 2 to 16 megabits, usually ~10.
If during a VOIP conversation a lot of traffic starts to some other client, the sound starts to "croak". As I understand it, it is impossible to configure QOS with different channel widths. I tried to cut traffic in Simple Queue, such as if the traffic exceeds 10 megabits for more than 10 seconds, we cut it to 5. It led to the fact that in such a situation it began to sometimes tear off the VOIP conversation along with the rest of the traffic.
In addition to the VOIP gateway, 4 computers go to the Internet through Mikrotik in office mode.
How best to deal with this situation?
I am not a big connoisseur of the theory of network technologies, unfortunately, therefore, I can’t imagine the solution to the problem at the root. And not an expert on Mikrotik, yes, but other soho routers are unlikely to be able to solve anything here at all.

Answer 1

QoS is not traffic cutting, QoS is prioritization
https://wiki.mikrotik.com/wiki/Voip

Answer 2

Give the warp a permanent limit.