Webcam not available at first but available after reboot

Hi altogether, :wave:

I have a question regarding a curious phenomenon I just got aware of.
Perhaps there´s someone out there who can help find some explanation.

My PC is Lenovo H520e and the webcam is attached via USB.

Normally when booting my system (Lubuntu 20.04.2) I can see my webcam LED flashing up a few times.

Today however that didn´t happen. :thinking:
When trying to use “cheese” the programme complained of “device not being found/available”.
Hmmm…

Using “lnav” I looked up the message logs.

And indeed I found the following:

May  4 09:42:23 rosika-10159 pulseaudio[2036]: Failed to find a working profile.                                                                                                                                                         
May  4 09:42:23 rosika-10159 pulseaudio[2036]: Failed to load module "module-alsa-card" (argument: "device_id="1" name="usb-Microsoft_Microsoft___LifeCam_HD-3000-02" card_name="alsa_card.usb-Microsoft_Microsoft___LifeCam_HD-3000-02" │
May  4 09:42:23 rosika-10159 kernel: [  236.409045] usb 1-1.2.4.3: 3:1: usb_set_interface failed (-71)                                                                                                                                   
May  4 09:42:23 rosika-10159 kernel: [  236.413303] usb 1-1.2.4.3: 3:1: usb_set_interface failed (-71)    

[...] repeated many times more

but lsusb listed the device as being connected:

Bus 001 Device 010: ID 045e:0779 Microsoft Corp. LifeCam HD-3000

I rebooted the system and everything was fine again. :kissing_smiling_eyes:

Does anybody have any clue as to what might have happened the first time :question:

Many thanks in advance.
Greetings
Rosika :slightly_smiling_face:

Could be that from cold boot it did not read it properly, you could add cheese to startup at boot, to see if it’ll kick in. Another webcam app to try is guvcview it’s in the repos has not got as many effects as cheese has, but I use it and it has never griped.

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It could also be that because it could not find it, is to why Pulse Audio did not load properly.

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@clatterfordslim:

Hi Mark,

thank you so much for your answers. :heart:

The first time it was cold boot indeed.
And pulseaudio seemed to be responsible for some problems like you said.

So you´re certainly right with your theses. :+1:

Well, so I´ll infer from that it seems there´s nothing to be done at the moment .
Anyway everything works fine now.
Thanks also for the tip referring to guvcview. I´ll look into it.

Many greetings
Rosika :slightly_smiling_face:

You’re very welcome Rosika, here to help if I can.

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Interesting. I have a similar (although not the same) problem with USB camera’s
The ‘built in’ is just about always found but any USB plugged in doesn’t register.
I’ll try a hot boot sometime and see if it makes a difference