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External USB Audio Interface and Windows 11, latency is a huge issue #3193

Description

@kn7k

Report preparation

  • I used the AI-assisted bug report tool (Help → Support → File an Issue)
  • I have attached a support bundle or log file

What happened?

Writing this after 4 days of troubleshooting and will try to summarize it here.
It is not necessary a bug as it could be a Windows 11 issue, but reporting it here since Aether Audio is a feature in Windows version.

Setup

  1. Windows 11, NUC i7 with 32gb RAM.
  2. 8600 network is hard wired.
  3. Network is Excellent
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Computer with AetherSDR running and PC Audio enabled

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  1. I was impressed with Noise reduction features I hear from speakers. Speakers connected to external Benchmark DAC3 HGC and to computer.

  2. I decided to continue to experiment and make Aether Audio work with my Headphones as well, so I purchased an external USB Audio Interface Scarlett Solo Gen4.

Problem statement

  1. Scarlett Solo Gen4 connected by USB straight to computer, no Hubs. Audio sounds great until I start to TX.

  2. Transition from TX to RX produce a "blip" sound with some delay that hard to quantify, but it is about 0.5-1+ seconds

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  1. I spent a lot of time with Gemini to research latency issue and could not find a way to reduce that delay.

  2. Scarlet Solo had a "Direct Monitor" settings that suppose to put audio straight to the headphones without delay. It is not a reality. Reducing Buffer size to a minimum that has a reported time 5.1 ms does not make any difference to what I hear. Basically changing Buffere size from 1024 to 16 does not make difference.Image

  3. I researched recommended ASIO driver and downloaded it, Set it up per recommendation, it does not change anything

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  1. About CW - CW works great when listening from radio, but with external audio interface CW sounds with shorten dots and dashes and uneven spaces, making it very "buggy". Tested it by playing messages from CWX.

  2. About Microphone. Same thing with huge delay. I can say "Hello" to a microphone and as soon as I finish saying it I can hear "Hello" in the headphones that I would estimate at least 1 second delay.

Note about Microphone
I spent a lot of time to troubleshoot Radiosport M20 headset connected to Scarlet Solo by XLR adapter with and without 48v bias - it does not work.
I found an old Heil Pro-Set Plus and microphone works.

Summary

At this point I can summarize that External USB Audio interface can be used for learning and experiments but cannot be used in CW or SSB Contests with Windows 11.

Sergey, KN7K

What did you expect?

No response

Steps to reproduce

See above

AetherSDR version

26.6.3

Radio model & firmware

8600 4.1.5

Operating system

Windows

OS version and hardware

Windows 11

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    CWCW keying, decode, and operationWindowsWindows-specific issueaudioAudio engine and streamingbugSomething isn't workingexternal devicesFlexControl, MIDI, serial port, USB peripheralsmaintainer-reviewRequires maintainer review before any action is takenpriority: mediumMedium priority

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