It seems like the noise problem was specific to one particular module--and there have been a fair number added since 2006 when that article was written.
However, if you want a definitive answer, I'm starting a collection to send me and my noise meter to the ISS.
Seriously, there probably is a fair bit of ventilation noise in much of the ISS--I believe the lack of gravity means they have to circulate all the air with fans to avoid pockets of CO2 etc. developing. However, there are also storage modules which, from the various video tours I've watched, are lined with lots of soft bags etc.
I've actually posted on Hadfield's Facebook page asking if he could do a post on what technology they used for the recording--I won't hold my breath but, who knows, we might get lucky.