Game audio being heard through my microphone by friends (over Discord)

So this is a more minor issue in the grand scheme of things, but it does annoy me and I was wondering if anyone had a solution to this.

Whenever I play audio, if I’m in a voice chat, the other people in the chat can hear my audio too. This includes games and music (Spotify etc).

I’m plugging my headset directly into the Line I/O ports on my PC’s chassis.

Here are my system specs, and I would appreciate it if anyone had any suggestions:

System:
  Host: humboldt Kernel: 5.16.14-1-MANJARO arch: x86_64 bits: 64
    Desktop: KDE Plasma v: 5.24.3 Distro: Manjaro Linux
Machine:
  Type: Desktop Mobo: ASRock model: B450M Steel Legend
    serial: <superuser required> UEFI: American Megatrends v: P3.60
    date: 11/03/2020
CPU:
  Info: 12-core model: AMD Ryzen 9 5900X bits: 64 type: MT MCP cache:
    L2: 6 MiB
  Speed (MHz): avg: 2940 min/max: 2200/4950 cores: 1: 3398 2: 3109 3: 3959
    4: 3931 5: 2071 6: 4288 7: 3336 8: 3971 9: 2066 10: 4615 11: 2066 12: 2058
    13: 3547 14: 3597 15: 3028 16: 3835 17: 2034 18: 2047 19: 2045 20: 2045
    21: 2543 22: 2864 23: 2059 24: 2058
Graphics:
  Device-1: AMD Navi 23 [Radeon RX 6600/6600 XT/6600M] driver: amdgpu
    v: kernel
  Device-2: Logitech Webcam C270 type: USB driver: snd-usb-audio,uvcvideo
  Display: x11 server: X.Org v: 1.21.1.3 driver: X: loaded: amdgpu
    unloaded: modesetting,radeon gpu: amdgpu resolution: 2560x1440~144Hz
  OpenGL: renderer: AMD Radeon RX 6600 XT (DIMGREY_CAVEFISH DRM 3.44.0
    5.16.14-1-MANJARO LLVM 13.0.1)
    v: 4.6 Mesa 21.3.7
Audio:
  Device-1: AMD Navi 21 HDMI Audio [Radeon RX 6800/6800 XT / 6900 XT]
    driver: snd_hda_intel
  Device-2: AMD Starship/Matisse HD Audio driver: snd_hda_intel
  Device-3: Logitech Webcam C270 type: USB driver: snd-usb-audio,uvcvideo
  Sound Server-1: ALSA v: k5.16.14-1-MANJARO running: yes
  Sound Server-2: PipeWire v: 0.3.48 running: yes
Network:
  Device-1: Realtek RTL8111/8168/8411 PCI Express Gigabit Ethernet
    driver: r8169
  IF: enp4s0 state: up speed: 1000 Mbps duplex: full mac: censored
  IF-ID-1: outline-tun0 state: down mac: N/A
  IF-ID-2: virbr0 state: down mac: censored
  IF-ID-3: vmnet1 state: unknown speed: N/A duplex: N/A
    mac: 00:50:56:c0:00:01
  IF-ID-4: vmnet8 state: unknown speed: N/A duplex: N/A
    mac: 00:50:56:c0:00:08
Drives:
  Local Storage: total: 1.36 TiB used: 921.02 GiB (65.9%)
  ID-1: /dev/sda vendor: Crucial model: CT500MX500SSD1 size: 465.76 GiB
  ID-2: /dev/sdb vendor: Toshiba model: HDWD110 size: 931.51 GiB
Partition:
  ID-1: / size: 457.09 GiB used: 363.7 GiB (79.6%) fs: ext4 dev: /dev/sda2
  ID-2: /boot/efi size: 299.4 MiB used: 288 KiB (0.1%) fs: vfat
    dev: /dev/sda1
Swap:
  Alert: No swap data was found.
Sensors:
  System Temperatures: cpu: N/A mobo: N/A gpu: amdgpu temp: 58.0 C
  Fan Speeds (RPM): N/A gpu: amdgpu fan: 0
Info:
  Processes: 512 Uptime: 1h 18m Memory: 31.27 GiB used: 8.08 GiB (25.9%)
  Shell: Zsh inxi: 3.3.14