"Can't place calls: No voice-capable modem available" message in Calls app

I ordered an received a Librem 5 off of eBay and received it last week. I am trying to get a VoIP account working in the Calls app using jmp.chat account, and I might have it configured (or mostly configured), but whenever I open the Calls app there is a red header message at the top that says “Can’t place calls: No voice-capable modem available.” I booted down the phone and removed the cover for the modem and the wifi card and confirmed it does have a BM818-A1 modem installed in it. Does anybody know why the Calls app is claiming that there is no BM818-A1 modem installed?

Check the HKS for mic and cam.

Are you referring to the physical switches on the side of the L5? If so, I have them all in the enabled position and have rebooted the Librem 5. I can see the “Wif-Fi” and the “Mobile” options in the Settings app, so I know that the OS is seeing the hardware. That said, I don’t have a SIM installed (yet). That shouldn’t make a difference, should it?

That error message is somewhat poorly worded as it doesn’t distinguish between “no modem” and “modem present, but no SIM” cases (although one could argue that a modem without SIM isn’t really voice capable ;)) - so not having a SIM installed definitely does make a difference there.

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although one could argue that a modem without SIM isn’t really voice capable :wink:

I was attempting to test VoIP calling with SIP before I invested money in another cellular bill. I’m fairly certain that if I keep the Librem 5, I’ll have to use T-Mobile, but the lack of VoLTE for calls is concerning because of the killing off of 2G and 3G. I know that Purism has promised that VoLTE is about to be working for everybody, but Purism has promised a lot of things, so I was trying to see if I could make the Librem 5 usable with VoIP and texting with a number from, for example, jmp.chat (although I would be willing to try other providers).

If you just want to try sip, then you can kill gnome-calls and then start it from the command line:
killall gnome-calls

run it several times until you have the output:

gnome-calls: no process found

then run:

gnome-calls -p sip

It is also possible to just disable the modem manager plugin for cellular in gnome-calls, but you might not want that at this point


if the sip account is not yet configured, it will give an error message saying that there is neither a modem nor a voip account

Um, no, sorry, this is a bug: you can call emergency services without a SIM (or with a SIM for the “wrong” MNO/MVNO) - but you will need it to recognise that there is a voice-capable modem in order for that to work.

I believe there is already an Issue filed about this. I think I raised it when a Librem 5 user reported here being in a situation that could have become life-threatening (or maybe did, I’m half a world away so not sure of the details).

I did the steps provided and the red banner does go away. That said, SIP calls work whether I’m running the Calls app normally (I.e with the alert banner) or with the “-p sip” argument (which runs it without the alert banner). I probably will get T-Mobile service and this shouldn’t affect me.

Thank you for your assistance!

Is that still true anywhere in the world? AFAIK SIM-less access to emergency services has been long disabled because of abuse in most (all?) countries.

They have? I know it’s been said it’s being worked on but I’ve yet to see anything more than that.

Fair question. Difficult to answer on behalf of the entire world.

Wikipedia says: false in Latin America and false in Britain (but does not provide a citation). https://en.wikipedia.org/wiki/Emergency_telephone_number#Emergency_numbers_and_mobile_telephones

Wikipedia implies: true in the US (and provides a citation)

Here’s one network in one country: https://www.vodafone.com.au/about/company/emergency-calls (albeit it claims to speak for all three networks)

In Australia emergency calls to Triple Zero can be made with or without an active SIM in your phone

And from the government itself https://www.triplezero.gov.au/triple-zero/other-emergency-numbers

It does not require a simcard or pin number to make the call, however phone coverage must be available (any carrier) for the call to proceed.

(that’s talking about calling 112 but on a mobile phone in Oz 112 and 000 should be interchangeable and equivalent for reaching emergency services)

It is possible that any of those citations could be out of date. It’s not something that I want to test for you. :wink: (There are enough idiots in my country calling the emergency services number just to get COVID PCR test results.)

From the perspective of the software designer, it would be safer to assume that absence of a SIM is not a barrier to making the call and let the carrier reject the call if that’s what local rules allow or require and the carrier is so configured.

The other scenario I mentioned (with a SIM for the “wrong” MNO/MVNO) is the more important and more likely scenario - in a large country with lots of network blackspots. So in that case the modem will probably have failed to register with the network, does have a SIM, but should still be able to call (emergency services).

As you say, abuse (/ spamming / hoax) is possible, although the mobile network will still have the IMEI (but that may be able to be forged). On a blackbox phone you don’t know what other details might leak if you call emergency services without a SIM, particularly if AML is supported by the phone (and the country).

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Is that still true anywhere in the world?

For whatever it’s worth, I can say that within the past 3 years my daughter has accidentally called 911 (I.e. the emergency number in the USA) on an old phone that did not have a SIM in it.


This argument what it does is basically only load the sip plugin in gnome-calls, and not the modem manager plugin, so basically it becomes a sip only device.

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