I would test Pd by recording a few seconds of [phasor~ 1], and measuring the number of samples per cycle. Obviously this should be the system sample rate, give or take floating point rounding error.
The worry in this thread is that Pd is playing at the wrong speed.
The only way this could happen is if [phasor~ 1] is running at the wrong speed, because in the demo patch, phasor~ is the only thing controlling the speed.
Therefore, if there is no evidence of phasor~ running at the wrong speed, then Pd must be playing the file at the true speed!
"But what if the system sample rate differs from the file's?" The file is at the lowest sample rate in common use. If Pd is playing it slower than Audacity, then Pd would have to be running below 44.1 kHz, which is unlikely to be supported in hardware. So I'm comfortable ruling that out (not to mention that scaling the phasor~ by the file's number of samples already accounts for this). Common scenario would be: 44.1 kHz file, 48 kHz system SR, without correcting for this then Pd would play faster, but that isn't the report.
is audacity running at 44100?
I'm pretty sure Audacity has no power to override the hardware sample rate. I've never heard of soundcards issuing separate, per-app interrupts at different rates (imagine how difficult that would be, to make it work, highly implausible). AFAIK Audacity does sample rate conversion when the file is at a different rate from the hardware... just like all other audio software.
Is it 100% guaranteed that Audacity is playing it at the right speed?