Hello Raymond!
Just half speed audio with the original pitch is very strange. Usually that
requries some good FFT-based time-stretching. The octave donw thing and half
speed is easy. It means: 1. wrong number of channels or 2. wrong internal
samplerate (much more likely). Does it sound clean? Did you check the format
of the file using the program file, or even better the sndfile-programs. I
believe, that's what they are called as packages on Debian (and probably other
distros).
The half speed issue should have nothig to do with suboptimal hardware.
Distorted sound, glithcy audio, pops while recording possibly, but even those
mostly result from bad settings to JACK or simply slow CPUs.
Sorry, I can't tell you more, but perhaps that might calm you down somehow,
or help you looking.
Kindest regards
Julien
--------
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