I lived in
Ireland for a while, and here are some of my observations as a name-obsessed outsider... There are very few native Irish speakers left, so while there has been great strides in resurrecting the language, Irish Gaelic is pretty much a second language for everyone. Thus said, how people pronounce things is pretty much based on (1) where they live (2) where their Irish language teacher (or teachers) was/were from and (3) how much they speak the language or are dedicated/interested in it. Some names are so popular that pretty much everyone pronounces them the same (
Aoife,
Niamh), or are so straightforward there isn't much debate (
Liam, Micheál).
I ran into a few Aislings in
Ireland, but no Aislinns; not that there aren't any; just that it's way less common. The Aislings I met were all pronounced /
ASH ling/, though the "ing" was slightly less pronounced than it is in American English. It was kind of like saying "I'm going fishing"-- sometimes it comes out "I'm goin' fishin'" if you're in a hurry, or depending on where you're from. The "ash" part sounds like halfway between /
ASH/ and /OSH/ to American ears, while the last "i" is somewhere between short "i" and long "i."
In Irish,
Aislinn would be slightly different from
Aislin, especially the farther north you go where the irish spoken there is closer to Scottish Gaelic. in Scottish, a word ending in -inn would actually have more of a sort of very brief "yeh" sound tacked onto the end that could sound sort of like -ing to some ears. But, since Irish names tend to get pronounced more like English, most people would probably just say /
ASH lin/. I've actually never seen
Aislin, but it would be pronounced like /
ASH lin/ too.
I spent a lot of time in
Ireland trying to get people to pronounce their Irish names and talk about them, and I've found that most people just assume their version is correct, even though it may be radically different from any other pronunciation... I think much of it had to do with trying to teach the dumb Yank about their language as anything else!
In the USA,
Aislinn seemed to be in danger of becoming the next
Caitlin-- I've seen it pronounced Icelyn, Acelyn, Aizlyn, Aizleen etc. ::groan::