More information here. Just the logs:
The one which is not working properly:
Sat Nov 21 2020 11:18:14.248 - //==============================================================================================
Sat Nov 21 2020 11:18:14.248 - ================================================================================================
Sat Nov 21 2020 11:18:14.248 - ================================================================================================
Sat Nov 21 2020 11:18:14.248 - vrmonitor.exe 1.7.15 startup with PID=11076, config=C:\VR\data\SteamVR, runtime=C:\VR\SteamVR_1.7.15
Sat Nov 21 2020 11:18:14.304 - Start Firmware Update (Device Index:0, Recovery:0, ForceAll:0, ForceFix:0).
Sat Nov 21 2020 11:18:14.305 - 1 Updates scheduled for LHR-7D03FB95 TrackedDeviceClass_HMD
Sat Nov 21 2020 11:18:14.305 - 1: FirmwareWizard_UpdateType_AudioBridgeUpdate: Existing:0, Required:288
Sat Nov 21 2020 11:18:14.318 - FirmwareWizard entering state FirmwareWizard_State_Headset_Start
Sat Nov 21 2020 11:18:14.318 - FirmwareWizard overwriting state to FirmwareWizard_State_ShutdownVRApps
Sat Nov 21 2020 11:18:20.489 - Delaying for 5000 milliseconds...
Sat Nov 21 2020 11:18:25.489 - Delay done
Sat Nov 21 2020 11:18:25.521 - FirmwareWizard entering state FirmwareWizard_State_Headset_Start
Sat Nov 21 2020 11:18:26.211 - 1: Probe for headset with serial LHR-7D03FB95. Found headsets: 1
Sat Nov 21 2020 11:18:26.211 - LHR-7D03FB95
Sat Nov 21 2020 11:18:26.211 - FirmwareWizard entering state FirmwareWizard_State_Headset_Progress
Sat Nov 21 2020 11:18:26.263 - FirmwareWizard_UpdateType_AudioBridgeUpdate: Existing:0, Required:288
Sat Nov 21 2020 11:18:26.313 - Headset Audio Bridge Update: C:\VR\SteamVR_1.7.15\tools\lighthouse\bin\win64\vivetools.exe abridge C:\VR\SteamVR_1.7.15\tools\lighthouse\firmware\htc\Encrypt_AUDIOBRIDGE_0120.bin
Sat Nov 21 2020 11:18:27.036 - Start
2 KB AUDIO_BRIDGE_WORK
4 KB AUDIO_BRIDGE_WORK
6 KB AUDIO_BRIDGE_WORK
8 KB AUDIO_BRIDGE_WORK
10 KB AUDIO_BRIDGE_WORK
12 KB AUDIO_BRIDGE_WORK
15 KB AUDIO_BRIDGE_WORK
17 KB AUDIO_BRIDGE_WORK
19 KB AUDIO_BRIDGE_WORK
21 KB AUDIO_BRIDGE_WORK
The one which is working fine:
Fri Nov 13 2020 16:52:28.299 - //==============================================================================================
Fri Nov 13 2020 16:52:28.299 - ================================================================================================
Fri Nov 13 2020 16:52:28.299 - ================================================================================================
Fri Nov 13 2020 16:52:28.299 - vrmonitor.exe 1.7.15 startup with PID=508, config=C:\VR\data\SteamVR, runtime=C:\VR\SteamVR_1.7.15
Fri Nov 13 2020 16:52:28.337 - Start Firmware Update (Device Index:0, Recovery:0, ForceAll:0, ForceFix:0).
Fri Nov 13 2020 16:52:28.338 - 1 Updates scheduled for LHR-A3C87B00 TrackedDeviceClass_HMD
Fri Nov 13 2020 16:52:28.338 - 1: FirmwareWizard_UpdateType_AudioBridgeUpdate: Existing:0, Required:288
Fri Nov 13 2020 16:52:28.350 - FirmwareWizard entering state FirmwareWizard_State_Headset_Start
Fri Nov 13 2020 16:52:28.350 - FirmwareWizard overwriting state to FirmwareWizard_State_ShutdownVRApps
Fri Nov 13 2020 16:52:34.855 - Delaying for 5000 milliseconds...
Fri Nov 13 2020 16:52:39.855 - Delay done
Fri Nov 13 2020 16:52:39.882 - FirmwareWizard entering state FirmwareWizard_State_Headset_Start
Fri Nov 13 2020 16:52:40.023 - 1: Probe for headset with serial LHR-A3C87B00. Found headsets: 1
Fri Nov 13 2020 16:52:40.023 - LHR-A3C87B00
Fri Nov 13 2020 16:52:40.023 - FirmwareWizard entering state FirmwareWizard_State_Headset_Progress
Fri Nov 13 2020 16:52:40.074 - FirmwareWizard_UpdateType_AudioBridgeUpdate: Existing:0, Required:288
Fri Nov 13 2020 16:52:40.125 - Headset Audio Bridge Update: C:\VR\SteamVR_1.7.15\tools\lighthouse\bin\win64\vivetools.exe abridge C:\VR\SteamVR_1.7.15\tools\lighthouse\firmware\htc\Encrypt_AUDIOBRIDGE_0120.bin
Fri Nov 13 2020 16:52:40.843 - Start
2 KB AUDIO_BRIDGE_WORK
4 KB AUDIO_BRIDGE_WORK
6 KB AUDIO_BRIDGE_WORK
8 KB AUDIO_BRIDGE_WORK
10 KB AUDIO_BRIDGE_WORK
12 KB AUDIO_BRIDGE_WORK
15 KB AUDIO_BRIDGE_WORK
17 KB AUDIO_BRIDGE_WORK
19 KB AUDIO_BRIDGE_WORK
21 KB AUDIO_BRIDGE_WORK
Done
As you can see, there is no differences (just the "Done" in the end") but time needed by the second one was like 40 seconds. The first one enters in a neverending update.