-verify', (task, should) => {
        let ramp = context.createBufferSource();
        let rampBuffer = createLinearRampBuffer(context, renderLength);
        ramp.buffer = rampBuffer;

        ramp.connect(context.destination);
        ramp.start();

        // Leave the playbackRate as 1 for the first half, then change it
        // to zero at the exact half. The zero playback rate should hold the
        // sample value of the buffer index at the moment. (sample-and-hold)
        ramp.playbackRate.setVal