audio delay?

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WMXZ

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I need some advice from audio experts, i.e. someone who is used to listen to teensy audio, being it audioboard or other audio devices

I setup following system
- ICS43432 I2S microphone sampled at 48 kHz (139 samples DMA interrupt interval)
- 139 to 128 sample conversion step (incl. 32 to 16 bit conversion)
- usb-audio to PC (windows 10)
- PC to logitech USB headset

All is working as expected
I only observe a noticeable delay when listening to sound (direct to ear and via teensy to headset)
What I expect is a delay in the order of 5 ms (2.9 I2S-DMA + 2 x 1 ms USB delays)

two questions:
- Is a 5 ms second delay noticeable (I don't think so as this would be an echo from 7.5 m reflection, which I never noted, but I may be wrong)?
- if PC is introducing additional noticeable delay, what can be done about it?

Edit:
did some measurements with matlab (recorded both ICS43432-Teensy AND Logitech mic simultaneously) and got delay of about 65 ms. ICS43432-Teensy is trailing headset mic by 65 ms.
Now question is where is this 60+ ms delay coming from?

Edit2:
I searched the internet but could not find any solution to this issue (e.g. unchecking 'listen to this device', etc.)
I forgot to mention that T3.6 is compiled with Serial-Midi-Audio flag
 
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I assume you're using windows?

Try accessing the Teensy USB Audio via ASIO4ALL driver rather than the built-in windows USB Audio Class. ASIO4ALL lets you specify the size of the software buffer on the computer side.
 
I assume you're using windows?

Try accessing the Teensy USB Audio via ASIO4ALL driver rather than the built-in windows USB Audio Class. ASIO4ALL lets you specify the size of the software buffer on the computer side.

Yes, it is Windows10
I tried this driver but for one reason or the other I do not succeed (my ignorance) to get the USB-Audio to use this driver. maybe wrong version, or misunderstanding of win10 procedures. For the moment I live with the delay (I'm not a musician or keen on karaoke etc)
 
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