Stefan wrote:

> First checked the signal with vtread | vtstat -i

That looks fine, no clipping.

> recorded a file without vttime and without vtresample.
> Converted to wav, displayed in SpecLab: Still the same effect!

> i made a wav file from CH2 and CH3, ... CH3 looks better than
> CH1 but some minor glitches are still there.

Curious.  Need to find out what those glitches on the SL
spectrogram actually are.  You've eliminated a lot of
possibilities with the tests so far.

> Should i ignore these faint effects?

Probably not, until we determine the root cause.  Otherwise
they'll cause a problem just when you don't need a problem!

Can you send or put on the web a short .vt file of ch1 and ch2,
(after vttime, vtresample) long enough to contain at least one
or two good glitches?

 vtread ... > file.vt

I'll have a look at it to see what those glitches actually are.

I haven't noticed anything similar but then, I've only really
looked at the sample rate stability and reliability of the card.

--
Paul Nicholson
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