USB and Bluetooth stops working + failed suspend – Ubuntu 20.04 on Dell Latitude 5490

I’ve been having the problems with my laptop ever since upgrading to 20.04 (from 19.10). I am uncertain whether these issues are related, but I’ve chosen to create one post in case there is a connection as some post seem to indicate they might be. These are the problems:

  1. Suspend fails occasionally
  2. USB ports and Bluetooth suddenly stops working
  3. Bluetooth device disconnects from headset

Regarding the first issue: According to the link in this answer, suspend problems is related to the Intel i7 Kaby Lake integrated graphics and kernel versions after 5.1. I applied the kernel parameters intel_idle.max_cstate=1 i915.enable_dc=0 to /etc/sysconfig/grub as described. While this fix seem to have reduced the suspend fail rate somewhat, it does not remove the issue. From what I can tell, suspend still fails when certain programs are running. For example, suspend seemingly fails every time when either the Evolution email client or Steam is running.

The second and third issues involves external hardware connected to the laptop. I have a Logi MX Ergo trackball mouse connected through a USB transmitter and Bluetooth, an external screen and webcam connected through a Dell DisplayLink D6000 docking station, and a Sennheiser noise-cancelling headset connected through Bluetooth.

The mouse works for the most part without problems when connected through USB transmitter or Bluetooth. The docking station has been troublesome from the start, but upgrading to 20.04 has made it worse: The external screen will sporadically disconnect for for a few seconds, before image returns. Sometimes the screen image will freeze and all external USB and Bluetooth devices are disconnected. When this happens, only the integrated screen and mouse pad will work. Only rebooting will get external devices working again. As stated above, the headset will not connect to Bluetooth after upgrading. The following error messages were printed during my last reboot after the USB and BLuetooth devices failed:

enter image description here

Seemingly these issues are related to the docking station, and seem to occur more often after suspend, thoug I have no idea whether they are related. Any ideas what may be causing the problem and how it can be resolved?

Below I’ve listed details of system configuration that may be relevant:

System:
  Kernel: 5.4.0-52-generic x86_64 bits: 64 
  Desktop: Gnome 3.36.4 
  Distro: Ubuntu 20.04.1 LTS (Focal Fossa) 
Machine:
  Type: Laptop System: Dell product: Latitude 5490 v: N/A 
  Mobo: Dell model: 0JKMV8 v: A00 
  UEFI: Dell v: 1.14.0 date: 07/15/2020 
CPU:
  Quad Core: Intel Core i7-8650U type: MT MCP speed: 800 MHz 
  min/max: 400/4200 MHz 
Graphics:
  Device-1: Intel UHD Graphics 620 driver: i915 v: kernel 
  Device-2: NVIDIA GM108M (GeForce MX130) driver: nvidia v: 455.23.04 
  Display: x11 server: X.Org 1.20.8 driver: modesetting,nouveau,nvidia 
  unloaded: fbdev,vesa resolution: 3440x1440~60Hz 
  OpenGL: renderer: GeForce MX130/PCIe/SSE2 v: 4.6.0 NVIDIA 455.23.04 
USB:
  Hub: 1-0:1 info: Full speed (or root) Hub ports: 12 rev: 2.0 
  Hub: 1-1:6 info: Genesys Logic 4-port hub ports: 4 rev: 2.1 
  Hub: 1-1.2:7 info: Genesys Logic 4-port hub ports: 4 rev: 2.1 
  Device-1: 1-1.2.2:9 info: Dell USB Receiver type: Keyboard rev: 2.0 
  Hub: 1-1.3:8 info: Genesys Logic Hub ports: 4 rev: 2.0 
  Device-2: 1-1.3.1:11 info: Bizlink USB2.1 Hub type: HID rev: 2.0 
  Device-3: 1-1.4:10 info: Logitech type: Mass Storage rev: 2.0 
  Device-4: 1-2:2 info: Logitech Unifying Receiver type: Keyboard,Mouse,HID 
  rev: 2.0 
  Device-5: 1-5:3 info: Sunplus Innovation Integrated_Webcam_HD type: Video 
  rev: 2.0 
  Device-6: 1-7:4 info: Intel type: Bluetooth rev: 2.0 
  Device-7: 1-8:5 info: Raydium Raydium Touch System type: HID rev: 2.0 
  Hub: 2-0:1 info: Full speed (or root) Hub ports: 6 rev: 3.0 
  Hub: 2-1:2 info: Genesys Logic USB3.1 Hub ports: 4 rev: 3.1 
  Device-8: 2-1.1:4 info: DisplayLink USB3.1 Hub type: <vendor specific> 
  rev: 3.2 
  Hub: 2-1.2:3 info: Genesys Logic ports: 4 rev: 3.1