The poem is a tiny snapshot of listening. The speaker opens with "Here we are," which sounds like a greeting, or maybe a small sigh, as if the crickets have shown up once more and everyone has to accept them. The sound itself is described as a "strange / dry din." That's an interesting pairing: "din" suggests noise and clutter, while "dry" makes it feel thin, brittle and scratchy, like rubbing paper together.
The repetition is what gives the poem its feeling. "Again in the afternoon," then "again in the night." The sound doesn't stop when the light changes, so it comes to seem constant, almost like part of the air. The short lines and the breaks between them mimic the pulsing, stop-start way crickets chirp.
The speaker's attitude isn't spelled out. It could be mild weariness, or quiet fascination at something so ordinary seeming strange. The mood is hushed, a bit uneasy, and hypnotic.