[Jack-Devel] output disconinuity: is it always a Jack XRUN?

Dear Jack devels,
I recorded for 1 hour a sine tone generator under JACK. I spotted two 
points in the resulting recording where a phase discontinuity occurs. My 
tone generator is based on a Chamberlin resonant filter, and I'm sure it 
works well for prolonged time (for the remaining 2h the signal is 
perfect). The recording was done at the analog output.

Question is: are these discontinuities undoubtedly a sign of XRUN? The 
console seem not to report any. Could it be something else?

In my understanding, when an XRUN occurs ALSA will go on reading the 
previous buffer.
Regards

Leonardo

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