Upload ffmpeg output to S3

When I make the next upload, if the duration of the clip is very short it generates a corrupt file and if it is a little longer, for example 19 seconds, it generates a file that starts from second 8

const passThroughStream = new PassThrough();
    const response = await new Promise((resolve, reject) => {
    const command = ffmpeg()
    .input(`${import.meta.env.BUCKET_URL}${m3u8S3}`)
    .inputOptions([`-ss ${TIME_OFFSET}`])
    .outputOptions([`-t ${end - start}`, '-c:v libvpx', '-c:a libvorbis', '-f webm'])
    .on('start', (commandLine) => {
            console.log('Spawned FFmpeg with command:', commandLine);
    })
    .on('error', (err, stdout, stderr) => {
        console.error('FFmpeg error:', err);
        console.error('FFmpeg stderr:', stderr);
        reject(err);
    })

    // Collect data into buffers
    const buffers = [];
    command.pipe(passThroughStream);
    passThroughStream.on('data', (chunk) => {
        buffers.push(chunk);
    });
    passThroughStream.on('end', async () => {
        try {
            const clipKey = `clip_${uuidv4()}.webm`;

            const buffer = Buffer.concat(buffers);
            const uploadParams = {
                Bucket: import.meta.env.BUCKET_NAME,
                Key: clipKey,
                Body: buffer,
                ContentType: 'video/webm',
            };
            await S3.send(new PutObjectCommand(uploadParams));

            resolve(new Response({ status: 200 }));
        } catch (error) {
            reject(error);
        }
    });
});

I hope to be able to create clips of maximum 1 minute from the hls transmission