VPN and VOIP Issue

Hello,

If anyone is familiar with VoIP with WireGuard can you help? I have a question, and I’m looking for feedback to improve my setup. I’m using my GL router, a strong model, on my home network connected by Ethernet with a top-ranked VPN, and I tested other top-ranked VPNs with similar results.

I use many VoIP services on my iPhone, On LTE using my WireGuard configuration, the VPN works perfect. With 50+ MPS speed and under 25 ms ping theres no sound lag or deaf spots when using voip apps

When I use my router’s Ethernet connected to the VPN WireGuard server, I get good speed, close to the speed I paid for 100+ MPS
25 ms ping, I have faster speed on my home network when doing the speed test on the same device close to the same ping (no, I don’t use double VPN the VPN is turned off when i connect to my home network on the iPhone. I also tried other VPN companies with the same outcome. Everything works well, but the VoIP calls

When I use any VoIP app, it’s almost unusable; there’s a deaf spot about every 45 seconds, which lasts 5 seconds or more.

What settings should I adjust on the network?The configuration of the WireGuard file? or any other tips to help with this VoIP bad quality problem.

Thank you for any help you can provide.

What model of GL router? Do you use it as wireguard server or client?