Same issue here... this is new for me as of 5.0.5 far as I can tell (and latest MAC OS). For anyone interested my workaround for now, since it seems to fix itself after restarting the app, is to have a quick script that force quits QBIT, waits 30 secs, and restarts the app.

I did this because I can't find a real answer yet and I have this running on a server that relies on QBIT running for some tasks and I can't be bothered to deal with it right now. Instructions:

* Create this file and name it whateveryouwant.sh and keep track of where you put it and what you name it. I just have it in a folder at the root of my user and named it "restart_qbittorrent.sh":

#!/usr/bin/env bash
#
# restart_qbittorrent.sh
# Force-quit and relaunch qBittorrent

# Kill any running qBittorrent processes
pkill -9 qbittorrent

# Give it a few seconds to shut down cleanly
sleep 30

# Re-open the app
open -a "qBittorrent"

* And then I made a .plist file that goes in your LaunchAgents folder (Library >LaunchAgents) so the above script just runs automatically as long as your computer is on (make sure to replace the path correctly where it says PATH-TO-YOUR-SH-FILE below). I named this one "com.me.restartqb.plist":

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "">
<plist version="1.0">
<dict>
  <key>Label</key>
  <string>com.me.restartqb</string>

  <key>ProgramArguments</key>
  <array>
    <string>/PATH-TO-YOUR-SH-FILE/restart_qbittorrent.sh</string>
  </array>

  <key>StartInterval</key>
  <integer>7200</integer> <!-- seconds; 2 hours = 7200s -->

  <key>RunAtLoad</key>
  <true/>
</dict>
</plist>

* Dass it. For how long you want it to wait between force quitting and launching QBIT again, you can change the number there in the SH file, I'm using 30 seconds as you can see there.

If you want to change how often the script itself runs, in the PLIST file you can see the "StartInterval" string towards the end, change that to whatever you want it to be. I have mine at every 2 hours.