Discord (VoIP) never works for me. When I speak, people always tell me I sound like a guitar or a robot, or that my voice is really glitchy. I can hear them fine though. I have tried changing the server, rebooting the PC/Router/Modem, and making a rule for it to bypass my firewall, but nothing seems to work. This has been going on since I moved house 2 years ago. Please help. P.S I use the desktop app.
This sounds like packet loss on the outbound leg of the connection. The issue is most likely that a user in the LAN is saturating the connection. Try isolating it to just your device to the router, and ensure only the VOIP program is running. If that works, start adding things back until you find the culprit - which may be p2p software or malware or something else. Once you find it, eliminate it, or run QoS to give it low priority.