Lenovo Legion T5 26AMR5 crackling sound when external sound card is plugged in via USB

Question

I bought a new Lenovo gaming PC and when I plugged in my external sound card via USB, my speaker started crackling. After a couple of days of googling I tried different things but they did not work. What I tried:

1. Plugging in my soundcard into another laptop (works fine)
2. Plugging in a different sound card into my gaming pc (crackling sound appears)
3. Tried different USB ports (still crackling)
4. Tried using a USB hub (still crackling)
5. Used another USB cable (still crackling)
6. Tried to change the minimum power settings of my CPU (from 5% to 100%). Did not work
7. Updated BIOS, Windows, sound card drivers
8. Changed the power settings of Realtek from the Windows registry (regedit)
9. Thought it might be a grounding issue so I plugged the PC chord into another socket.
10. I changed my HDMI cable just in case it was interfering.
11. Edited the sound settings (disabled enhancements and exclusive mode)

What does work:

1. Plugging in headphones via a USB port works fine
2. When the sound card is plugged in, all sound coming from the PC is fine but the crackling still remains in the background.

I really like my PC and I do not want to send it back. However, I have seen similar issues in the forums of Lenovo. I am running out of ideas and any suggestions are very welcome.

One thought on the grounding issue: my pc is standing on my desk, next to my monitor. Is there anything I can do to avoid any excess voltage/current coming out of it?

My devices:

1. Lenovo Legion T5 26AMR5
2. Focusrite Scarlett 2i2 (3rd Gen)
3. BENQ 35" curved monitor

Answer 1

[EDIT - FINALLY RESOLVED!!]

After I replaced my PC with another unit (same version) the issue still persisted. This led to the conclusion that the issue was a ground-loop. I ordered a USB isolator to ground any current from my PC to my audio interface. This did not work. Then I ordered an audio isolator and I placed it in between my speakers jack cables and the input of my audio interface. I could not find an isolator that worked on Jack cables, so I had to buy a Jack-to-mini-Jack converter. This removed the crackling/buzzing sound. If you want to use a better audio isolator for recording purposes, I bought the Behringer MICROHD Hum Destroyer HD400 device and it worked. This was a tough journey, but an interesting one.

Hope this helps you!

---

I called Lenovo Tech Support and they tried:

1. Install additional drivers
2. Discharge the unit's excess voltage by unplugging it and holding down the power button for 60 seconds
3. Reinstall Windows
4. Update BIOS
5. Disable audio through BIOS settings

Nothing seemed to work. In the end, Lenovo said it could be a 50-50 between a hardware issue from the motherboard or a compatibility issue between Lenovo Legion T5 and Focusrite Scarlet 2i2 (3rd Gen).

I am very sad I could not resolve the issue. I have to return my PC.