Random video lagging in push streams

[lpvideo]

Hi, I read the guides published in the github repository and I found a singular problem with nginx rtmp module running on windows 11 x64. I have several rtmp applications in the nginx.conf file. Only in the application that pushes to facebook, youtube, hls and on a local relay application I found that, with the same network and devices that transmit, randomly the stream starts to lose frames (which are not reported in the dashboard as "dropping frames") and the encoder (Vmix 27 in my case) starts to flash.
I tried to change machine, network and increase the chunk size but the problem is not solved.
Obviously I opened ports 1000 and 9001 for youtube and facebook and I use sTunnel for facebook rtmps authentication.

This is the rtmp part of my .conf file, I replaced the rtmp keys for privacy.

rtmp {
    server {
	listen 1935;
	chunk_size 6096;

	application stream {
	        live on;
		interleave on;
		meta on;
		session_relay on;
		max_connections 150;
	    	record_path recordings;
		record_suffix all-%d-%b-%y-%T.flv;
		# record_interval 30s;
		# record keyframes;
		# codes for the auto push(forwarding port 1000 for facebook);

		push rtmp://a.rtmp.youtube.com/live2/XYZ;
                 push rtmp://127.0.0.1:1000/rtmp/FB-XYZ;
		push rtmp://127.0.01/hls;
		push rtmp://127.0.0.1/emissione;
		}

	application ponte1 {
	        live on;
		interleave on;
		meta on;
		session_relay on;
	    	record_path recordings;
		record_suffix all-%d-%b-%y-%T.flv;
		# record_interval 30s;
		# record keyframes;
		}
	
	application ponte2 {
	        live on;
		interleave on;
		meta on;
		session_relay on;
	    	record_path recordings;
		record_suffix all-%d-%b-%y-%T.flv;
		# record_interval 30s;
		# record keyframes;
		}
	
	application ponte3 {
	        live on;
		interleave on;
		meta on;
		session_relay on;
	    	record_path recordings;
		record_suffix all-%d-%b-%y-%T.flv;
		# record_interval 30s;
		# record keyframes;
		}
	
	application ponte4 {
	        live on;
		interleave on;
		meta on;
		session_relay on;
	    	record_path recordings;
		record_suffix all-%d-%b-%y-%T.flv;
		# record_interval 30s;
		# record keyframes;
		}
			
	application emissione {
	        live on;
			allow publish 127.0.0.1; 
            deny publish all;
			# allow 127.0.0.1;
            # deny all;
		interleave on;
		meta on;
		}


	application hls {
	        live on;
		hls on;
		hls_nested on;
		hls_cleanup on;
		meta copy;
		# hls_sync 100ms;
		hls_type live;
		hls_fragment 5s;
		hls_playlist_length 30s;
		hls_path temp/tmp_hls;							# <----- 
		hls_fragment_naming system;

		hls_variant _low BANDWIDTH=288000;	# Low bitrate, sub-SD resolution
		hls_variant _mid BANDWIDTH=448000;	# Medium bitrate, SD resolution
		hls_variant _high BANDWIDTH=1152000;	# Higher-than-SD resolution 
		hls_variant _higher BANDWIDTH=2048000;	# High bitrate, HD 720p resolution
		hls_variant _src BANDWIDTH=4096000;	# Source bitrate, source resolution
		}
	}
}

Thanks in advance for your help.