Here is the sentence:
With this app, You can add audio effects, and you can also punctuate proceedings with the sound of a flying aeroplane or an air horn.
The sentence is from a DJ app which lets its users access a great number of sound tools on their mobile.
I know the lexical meanings of both punctuate and proceedings, but I am not sure what do they mean when used together in this context. Is it about adding special sounds to signify intervals between events or does it simply mean adding some sounds which are played intermittently?