Recently, I've been using Siri in Japanese to set cooking timers. I've noticed she pronounces the「フ」in「十五分」clearly as /hu/, not /fu/.
Old Japanese does not have /h/, but rather /ɸ/ (preserved in modern fu, /ɸɯ/), which has been reconstructed to an earlier /*p/.
It represents the phoneme /hu͍/, although for phonological reasons, the actual pronunciation is [ɸu͍].
The sound sample in the Wikipedia article does sound more like /fu/.
While I understand it's basically the same phoneme for the Japanese, I do hear the difference. Hence the question.
Is the Siri's variant acceptable?