BC127-HD CVC License Problem?


I bought a BC127-HD from digikey with the following address and licenses:

APTX=3D6C EB29 FC65 EA03 0000
CVC=3465 57F8 42AE FC81 0000

Normal operation in HFP works fine, but after I enable CVC with the commands


No audio from the microphone is transfered any more. Are there other commands that I have to use to make CVC work?
For me it seems strange that the CVC license is the same that I got after using the CVC-Enabler on other devices.

Is the CVC license correct? And if not how can I get a correct one?

thank you

Hi oesv31,

The CVC license read from the command is a demo license key which does not match with your BC127 BT address.

We offer a tool on the Source (link below) which allow you to load a demo license for the CVC demo. Since CVC and BT address must match before the demo can work, thus this tool will overwrite your BC127’s BT address. Please note, the BT address is not reversible.


Hello Sierra_2hufan

For me this sounds like the -HD modules do not come with a CVC licence. Is that correct?
So I have the following questions:

  • which module do I have to buy to get the CVC license out of the box?
  • which CVC license do I have to buy to use it with the -HD modules ? BCSW-CVC-HF-2M-Fx ? 1 Mic / 2 Mic ? handsfree / headset?
  • How to switch between 1 Mic / 2 Mic mode CVC?
  • Where to buy those licenses ?

thank you

Hi oesv31,

Sierra offers a CVC enabled SKU for BC127, you can check further details with your supplier. Regarding BC127-HD, unfortunately Sierra does not offer the same configuration as BC127, you can purchase the CVC license from Qualcomm and then use AT-cmd to load the key to the module. Hopes this answer your enquiry.

I have purchased the cVc license through Future Electronics… If you need a contact let me know!


Would you mind sharing your contact’s info at Future Eletronics? I have been getting nowhere with regards to licencing cVc from Sierra/Qualcomm.


Hi Theodore, below is my guy at Future

Ask Thomas for a License Key Request Form for Bluetooth Based Products excel sheet

He’s great and should be able to get you going…

Are you guys working on handsfree? If so, perhaps we can collaborate?

Thomas Suchorski

Product Manager – Future Connectivity Solutions

237, boul. Hymus

Pointe-Claire QC H9R 5C7

T 514.694.7710 .EXT 5638

Toll Free: 1.800.767.1458 ext. 5638

F: (514) 428-7613

He sold our cVc licene to us….


Thanks a bunch! I will reach out to him.

I’m working on an in-car Bluetooth solution for older BMWs . This solution makes use of the infotainment system bus in order to provide an OE-like experience.

In my prototype testing, my users have found that there is a good amount of background echo picked up by the BC127. Unfortunately, cVc is the only way that I have been able to get rid of it, and even then it’s not a fool-proof fix.


Hey Ted, no problem! Hope they can help. I think they have a 25 license minimum!

Otherwise you can use the DEMO prog to add cVc. But there is no going back fi you do!

Our product is also vehicle solution! We started out with a 2 mic solution but the BC127 HD does not support 2 mics in a handsfree environment. YET! Hopefully they will add the code to allow 2 mics soon!

The cVc is amazing once implemented! Virtually all background noise is gone! What type of Mics are you using and did you go analog or digital?


25 is fine! Do you know what those ran you guys, more or less?

Yeah, I’ve checked our the website in your profile – you guys are doing awesome work. I’m more focused on the users who don’t want to lose the original I.C.E. experience, and would rather augment it.

cVc still doesn’t fully resolve the issue, for me. I’m using an analog mic, the one that came with the car, actually. It seems to pick up the echo at the beginning of my statements and then cancel the rest out. Oh well, it’s still better than the clear and consistent echo that I get without it :).



Do you remember if the BCSW-CVC-HF- SKU is what you guys purchased from Future Electronics? Everyone I ask comes back with “You should buy the cVc enabled module from Sierra”, but those have a 16 week lead time!



I followed your instructions to update melody with the demo aptx and cvc license, but it is not working.

My config after the update (which was marked successful):

get local_addr
aptx=3061 416a 59d8 ea03 0000
cvc=3465 a979 bc24 dc99 0000

What should I do next to use the cvc demo license?
Others hear terrible echo (of their own voice) when using BC127 as car hands-free.

When I tried enabling the cvc in HFP_CONFIG, nothing can be heard from my voice.

I know this is an old thread, but someone might give me some light, as sierra refused to help (in spite the fact I bought these devices directly from them).

It seems they don’t understand me, as always telling me to go to the distributor directly (however I have bought directly from Siearra).

Thank you if you could help me anyhow.

Did you use the Melody Demo License tool? It doesn’t appear that your MAC ID was updated to one of the demo ones (20FABB000180 - 20FABB000186, IIRC). This disparity would cause you not be heard.


Yes, I’ve used that tool and it was updated Melody successfully. (At least it gave me that message). I have no idea why it didn’t change my local mac to match with the demo license. :frowning:

Future Electronics is not able to provide anything. :frowning:

You might need to first go to melody 6.1.5 before using this license tool

Thanks! Will definitely give that a try.