audio streams play high latency

[uzunenes]

Hi,

We've been using the VAPIX API to play audio streams, but we're experiencing an ~2-3 second latency issue. How can we reduce this latency?

Here is the command we're using:
curl --anyauth "http://USER:PASS@IP/axis-cgi/mediaclip.cgi?action=play&location=/etc/audioclips/my_voice.mp3&volume=100&repeat=0"

Hardware: AXIS C1310 E network horn speaker

Note: The .mp3 file does not include any silence at the beginning or end.
Note: We have a low-latency network LAN system.

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[vivekatoffice]

Hi @uzunenes ,
For other clips on the AXIS C1310 E network horn speaker, what response time you get?

[uzunenes]

Hi, @vivekatoffice,

I made the clients we are using the same, so a proper comparison can be made now. Could you check it again?

Could we be focusing on the wrong areas? I think we should be comparing the total times. Also, these request times may not significantly affect the delay in the speaker's play sound. (~2-3 sec)

[Serhat60Karaca]

Hi @uzunenes , I am not sure but you may need to check the Queuing time. For my snapshot, it is 0.36ms and in your case, it is 108ms.

Content download: 0.55ms vs 618ms 😢

Hi @vivekatoffice ,

Could you please help me understand the relationship between the time it takes to queue the request to play audio through the speaker in the browser and latency of playing audio? Isn't that about browser? milliseconds did not seem problem to me idk

[vivekatoffice]

Hi @uzunenes / @Serhat60Karaca ,
I agree with you on Queuing time comparison. I don't think it is related. My point is only that my_voice.mp3 which you are using may cause a delay if you send compressed audio (like MP3), the speaker will need to decode it, which can add a small delay. Sending uncompressed audio can reduce the decoding time.

That was my point here 🥲 . Do you find that default audio clips play without any delay?

Hi @uzunenes , For other clips on the AXIS C1310 E network horn speaker, what response time you get?

[uzunenes]

Hello @vivekatoffice,
I tested the device with its default audio clips and a 22kHz mono WAV file that I created.

I connected my computer and the Axis horn speaker to the same NTP server.
There is less than a 100 ms time difference between when I send the MQTT message and the Axis device event logs, meaning the startup delay is very minimal.

However, the speakers start playing the audio one second later. I am measuring this by recording a video. Is there any way to reduce this delay?

[vivekatoffice]

Hi @uzunenes ,
Please upload the speaker server report and the video you recorded. I have not faced this myself but I will ask if someone else faced the same issues.