webApi FTP mp3 转文件流在线播放

[HttpGet]
public async Task<HttpResponseMessage> GetCallRecordAudio(int id)
{
    var info = ModelOpretion.FirstOrDefault<BaseCallRecordInfo>(id);//查询对于的通话记录
    if (info.FID > 0)
    {
　　　　 //info.FRecordHttp FtpUrl
        var bytes = await FileUpLoad.GetFileStreamAsync(info.FRecordHttp, ftpUser, ftpPwd);                
        HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
 　　　　//response.Content = new StreamContent(stream) 通过流实例化的Conent文件为空
        response.Content = new ByteArrayContent(bytes);
        response.Content.Headers.ContentLength = bytes.Length;
        response.Content.Headers.ContentType = new MediaTypeHeaderValue("audio/mpeg");
        response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("inline")
        {
            FileName = $"{info.FCId}.mp3"
        };
        return response;
    }
    else
    {
        return null;
    }
}

public static async Task<byte[]> GetFileStreamAsync(string ftpUrl, string ftpUser, string ftpPwd)
{
    try
    {
        WebClient webClient = new WebClient();
        webClient.Credentials = new NetworkCredential(ftpUser, ftpPwd);
        return await webClient.DownloadDataTaskAsync(new Uri(ftpUrl));
    }
    catch
    {
        return null;
    }
}