This video probably best describes the issue. I can only have channels in 1 server muted at a time, remuting 1 channel remutes all of the previously muted ones but unmutes every other servers muted channels https://0x0.st/iq8D.webm#nsfw

Thanks for reporting this. I've actually already fixed it for the next release, before you reported it :)

I should add that this is a problem only in the local client state in Ripcord -- it's not messing up anything on the server. If you restart Ripcord, you'll see that the list of muted channels is correct.