Disconnects every round

With no rhyme or reason, the game, usually every round, will desync and auto-disconnect after 60 seconds. I can rejoin after that time interval and, more often than not, get random lag spikes or disconnects in the next round anyway. So far, I've:

• Turned off my firewall while playing, still got disconnects
• Verified my game files, still got disconnects

Relevant info:

• Always playing on casual, official Valve servers
• Playing the Linux (Arch btw) build with Vulkan
• No mods, only FlawHUD, custom hit and kill SFX and a mastercomfig with the high preset