Poor call quality is usually linked to internet performance. Here’s what to try:
Switch to a stronger Wi-Fi or 4G/5G network.
Avoid public networks with weak signal or high congestion.
Close background apps that may consume bandwidth (e.g., streaming, downloads).
Restart the app and/or phone.
VoIP quality depends heavily on real-time bandwidth and network stability. If you can video call reliably, KeepMyNumber should also work smoothly.