I've just been listening to the recordings linked to from this thread, and with the exception of The Corries, all of them pronounce "hubhan," phonetically speaking, as if it were spelt "huvan" - but The Corries pronounce it, phonetically speaking, as if it were spelt "hovan." (So The Corries pronounce "hòbhan" and "hubhan" identically to each other, whereas none of the other singers do).

Are both pronunciations correct (e.g. due to different regional dialects of Gaelic) - or have the Corries mispronounced it?

Dave