Fillum?

I find the fact that 'film' is pronounced 'fillum' in most of Ireland quite charming. Because there is really no way in Irish Gaelic to pronounce that weird letter combination, a quick 'uh' (schwa) is stuck between them so you can wrap your tongue around the letters. It's not written, but appears when the letters l, n, or r get bumped up against b, c, g, or m. Pronounce both sounds separately, with that auxiliary vowel sound stuck in there as you need to.

For example, banbh (piglet) is pronounced roughly 'ban-uhv' (don't pay any attention to that weird 'bh' combination yet! Just trust me that it's 'v'). And bolg (stomach) is roughly bullog. I don't think that I'd be misunderstood if I didn't insert the 'uh' sound and just said bol-g, but I imagine that it would be seen as a quaint mispronunciation that added to our "American" accent in Gaeilge.

American English (most dialects, anyway) don't have this pronunciation issue. We just run the sounds together in most cases, so 'film', 'berg', 'calm' don't need this auxiliary vowel sound inserted. I have heard some British English speakers with the extra syllable, however.