Hi,
you may break down the pipeline to see if the issue is in decoding or encoding. Please try
gst-launch-1.0 rtspsrc location="..." latency=0 ! application/x-rtp,encoding-name="H265",payload=96 ! queue max-size-bytes=0 ! rtph265depay ! video/x-h265, stream-format=byte-stream,framerate=25/1 ! h265parse ! queue max-size-bytes=0 ! nvv4l2decoder enable-max-performance=true disable-dpb=1 ! nvoverlaysink sync=false
And see if video playback is smooth. Certain h264 stream is not suitable with disable-dpb=1. As comparison, you may also try
gst-launch-1.0 rtspsrc location="..." latency=0 ! application/x-rtp,encoding-name="H265",payload=96 ! queue max-size-bytes=0 ! rtph265depay ! video/x-h265, stream-format=byte-stream,framerate=25/1 ! h265parse ! queue max-size-bytes=0 ! nvv4l2decoder enable-max-performance=true ! nvoverlaysink sync=false