Annoying sound effects

A thin electronic tone returning every two seconds, forever. This is the one most edits want, because the silence between the beeps is long enough to hope it has stopped and short enough that it never does.

Hollow plinks into a steel basin at intervals that never settle. The unevenness is what stops an ear filing it away as rhythm, so attention keeps being dragged back to it.

Two blocks of packing foam worked against each other into a high stuttering squeal. It sits in the band that makes people physically flinch, so a couple of seconds is usually plenty.

One tiny pair of wings beating near the microphone, wandering closer and further away. It reads instantly as something you cannot swat, which no static tone ever manages.

Steel dragged across glazed ceramic in one slow pass. The screech carries a rough grinding layer underneath, and that grind is the part people react to rather than the pitch.

Hard dry clicks about twice a second, never quite in time. Quiet enough to hide under dialogue and repetitive enough to become the only thing an audience is listening to.