altered audio when other app recording audio in same time

[lordiu]

[Reid-n0rc]

Context

For mic-based capture the app records via AudioRecord and deliberately picks the least-processed input source it can (MicRecorder.chooseAudioSource): UNPROCESSED on API 24+ when the device advertises support, otherwise VOICE_RECOGNITION. Both aim to avoid AGC / noise-suppression that would distort FT8 tones. (There's also a separate direct-USB-audio input path that bypasses AudioRecord entirely.)

When a second app opens the microphone at the same time, Android's concurrent-capture rules can change what our stream gets — the input can be re-routed, ducked, or have effects applied by the other app's chosen source — which would explain "altered audio". Knowing exactly which input and which other app is involved will tell us whether this is a routing issue or a processing (AGC/NS) issue.

Questions for @lordiu

1. Which input is FT8AF using — the phone's built-in mic, a USB audio device/dongle, or a Bluetooth input?
2. What is the other app that's recording at the same time (e.g. a voice recorder, an active phone/VoIP call, screen recorder, a streaming/broadcast app)?
3. How is the audio "altered" — quieter or louder, distorted/clipped, or just decoding far fewer signals? Does the waterfall look different?
4. Does it recover on its own once the other app stops recording, or does it stay altered until you restart FT8AF's capture / the app?
5. Phone model + Android version?

[lordiu]

Questions for @lordiu

1. Which input is FT8AF using — the phone's built-in mic, a USB audio device/dongle, or a Bluetooth input?

i use wired audio through 3.5mm jack

2. What is the other app that's recording at the same time (e.g. a voice recorder, an active phone/VoIP call, screen recorder, a streaming/broadcast app)?

any app that recording audio

3. How is the audio "altered" — quieter or louder, distorted/clipped, or just decoding far fewer signals? Does the waterfall look different?

waterfall looks different, more noise, signals are also a bit louder

4. Does it recover on its own once the other app stops recording, or does it stay altered until you restart FT8AF's capture / the app?

yes, immidiately

5. **Phone model

sm-a505

[patrickrb]

Nice, I just created #597 for this after encountering the same issue! Thanks for reporting!