Sollux Captor

So, in the Capital H AU, there is indeed a troll to human language barrier, and as such, a distinctive Alternian language. It is actually quite dissimilar from any spoken human language, and uses a lot of sound making features that humans do not possess - namely a lot of weird insect-like chirruping and clicking, with the occasional mixture of something resembling animal growling.

For funzies, I've compiled some examples of bug sounds that one could frequently find in the Troll vocabulary. Even while speaking English, the Alternian accept tends to involve the subtle addition of these sounds to human words.

Fair warning, most of these are videos of real insects, so if you hate bugs don't look.

CICADA GROWL
Imagine this but with an undertone of a predator's growl. This is a sound a troll might make while agitated, and will tend to flavour their words.

CRICKET CHIRPING
More of a neutral toned chirp, this is probably the sort of sound that appears a lot in the actual language, though trolls can affect it with different tones and pitches by speaking.

SOFT CRICKET CHIRP
A gentler sort of chirp that would have more positive/friendly verbal connotations. A longer, trilling of this is what would be considered a troll purr.