你好 我rtsp在vlc上播放正常，项目启动后这里无法播放：
org.bytedeco.javacv.FrameGrabber$Exception: avformat_open_input() error -875574520: Could not open input "rtsp://admin:123456@XXX.XX.XX.XX:XXX/cam/realmonitor?channel=17&subtype=1". (Has setFormat() been called?)
at org.bytedeco.javacv.FFmpegFrameGrabber.startUnsafe(FFmpegFrameGrabber.java:876)
at org.bytedeco.javacv.FFmpegFrameGrabber.start(FFmpegFrameGrabber.java:801)
at org.bytedeco.javacv.FFmpegFrameGrabber.start(FFmpegFrameGrabber.java:796)
at com.zj.thread.MediaConvert.convert(MediaConvert.java:113)
at com.zj.thread.MediaConvert.run(MediaConvert.java:402)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Error: [flv @ 0x7fe0bb20ca00] No streams to mux were specified

org.bytedeco.javacv.FrameRecorder$Exception: avformat_write_header error() error -22: Could not write header to ''
at org.bytedeco.javacv.FFmpegFrameRecorder.startUnsafe(FFmpegFrameRecorder.java:900)
at org.bytedeco.javacv.FFmpegFrameRecorder.start(FFmpegFrameRecorder.java:406)
at com.zj.thread.MediaConvert.convert(MediaConvert.java:143)
at com.zj.thread.MediaConvert.run(MediaConvert.java:402)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
请问这个什么原因呢，通道1就可以正常播放