rtsp h264 client

[clyu2000]

I am using VLC to show rtsp h264 streaming , but vlc will show “[013dfea0] avcodec decoder error: more than 5 seconds of late video -> dropping
frame (computer too slow ?)” after a while.
I catched Ethernet packets using wireshark , parse the RTP packet and compare timestamp, no found abnormal timestamp , moreover the sequence number of RTP packets is continuous and no packet lost.
I save RTP playload h.264 streaming to file using wireshark, after that , playing the file uses the command :
ffplay.exe -framerate 4 c:\Users\clyu2\from_10.130.11.38_47526to10.130.11.4_55964.264

it decode normally and no error happen

if using SMPlayer acting as RTSP client , SMPlayer works well and shows smoothly

So what's the reason that VLC show “more than 5 seconds of late video”

I debug the issue for 2 months, and no idea about that.

Thanks for your kindly helping!