This particular sentence doesn't have any audio, but Duolingo is still presenting it for "Type what your hear" exercises - it's not a connection speed issue, it's a mixup that occurred when the new audio recordings replaced the old set of recordings.
The issue has been reported to the engineering staff at Duolingo, and it is being looked into.
I've heard the phenomenon called "h-prothesis". AFAIK, it happens here, not because of consecutive vowel sounds, but because the feminine possessive pronoun "her" found in a, lena, etc, prothesizes... er, adds on that "h" at the beginning. "Like his father" would be Cosúil lena athair because the masculine doesn't cause h-prothesis.
I have also heard it called 'the caducous h'. When people start making up lots of names it means they do not understand what is going on. It is not regarded as a mutation, but it works just like one in that certain words cause it depending on what the next word starts with. However, if you learn Welsh you will see that it really fits in as a mutation because ei, their equivalent of a, 'her', causes a mutation to certain consonants and adds an h before vowels.
Ei thad 'her dad'
Ei heliffant 'her elephant'
But no one actually seems to know the origin.