Re: Win11 ??

> Good question. In my experience from dealing with digital audio, discontinuities in an audio stream can definitely be very noticeable, for example when you take a long sample and try to loop it. If the start and end position sample amplitudes differ too wildly you do get a very clear crack in the sound.

Very noticeable in looped sampled sound - but especially because it is a repeating event.

> Mind you, a rapid discontinuity in digital audio would be similar to a delta impulse which produces high amplitude bins across the entire FFT. Think of how a single unity sample in the time domain produces all unity samples in the frequency domain.

This kind of discontinuity is what shows up in the FFT of the incoming buffer - the expected signal is still present, but it has very broad skirts, instead of the expected very narrow spike, for the reference carrier signal. 

Very much like an impulsive sound would produce. That’s why I suspected dropped samples.

I decided to “trick” the C module doing my data collection with the M$ MMI API. I give it a buffer 6x larger, and run at 48 kHz, then downsample on the receiving end in my Lisp code.

It is working very well now. But waiting to see if the “events” will still occur, starting in about 50 minutes from now…

- DM

> On Sep 3, 2025, at 07:27, Yuri Davidovsky (as work at disclosure dot ie) <[email protected]> wrote:
> Good question. In my experience from dealing with digital audio, discontinuities in an audio stream can definitely be very noticeable, for example when you take a long sample and try to loop it. If the start and end position sample amplitudes differ too wildly you do get a very clear crack in the sound.
> Mind you, a rapid discontinuity in digital audio would be similar to a delta impulse which produces high amplitude bins across the entire FFT. Think of how a single unity sample in the time domain produces all unity samples in the frequency domain.
> 
> 
> Or alternatively, note how a lightning bolt that lasts for a minuscule amount of time creates a noticeable crack on an AM radio across the entire band on any station you are tuned to. So yes, just a single sample going off track can be very noticeable to a human ear, but whether that is the problem you are dealing with is not very clear at this time.
> 
> 
>> On 3 Sep 2025, at 15:37, David McClain <[email protected]> wrote:
>> 
>> But honestly, would you even notice an audio disruption occurring every 76 minutes? It might be just a short audio crack, not noticeable to human listening.
> 
> 
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