diff --git a/nixos/tests/mediamtx.nix b/nixos/tests/mediamtx.nix
index 7f7d40d3e12a..a815efccfdfa 100644
--- a/nixos/tests/mediamtx.nix
+++ b/nixos/tests/mediamtx.nix
@@ -1,5 +1,8 @@
 { pkgs, lib, ... }:
 
+let
+  rtmpUrl = "rtmp://localhost:1935/test";
+in
 {
   name = "mediamtx";
   meta.maintainers = with lib.maintainers; [ fpletz ];
@@ -23,8 +26,8 @@
           DynamicUser = true;
           Restart = "on-failure";
           RestartSec = "1s";
-          TimeoutStartSec = "10s";
-          ExecStart = "${lib.getBin pkgs.ffmpeg-headless}/bin/ffmpeg -re -f lavfi -i smptebars=size=800x600:rate=10 -c libx264 -f flv rtmp://localhost:1935/test";
+          TimeoutStartSec = "30s";
+          ExecStart = "${lib.getBin pkgs.ffmpeg-headless}/bin/ffmpeg -re -f lavfi -i smptebars=size=800x600:rate=10 -c libx264 -f flv ${rtmpUrl}";
         };
       };
 
@@ -33,12 +36,13 @@
         after = [ "rtmp-publish.service" ];
         bindsTo = [ "rtmp-publish.service" ];
         wantedBy = [ "multi-user.target" ];
+        unitConfig.StartLimitIntervalSec = 0;
         serviceConfig = {
           DynamicUser = true;
           Restart = "on-failure";
           RestartSec = "1s";
-          TimeoutStartSec = "10s";
-          ExecStart = "${lib.getBin pkgs.ffmpeg-headless}/bin/ffmpeg -y -re -i rtmp://localhost:1935/test -f flv /dev/null";
+          TimeoutStartSec = "30s";
+          ExecStart = "${lib.getBin pkgs.ffmpeg-headless}/bin/ffmpeg -y -re -i ${rtmpUrl} -f flv /dev/null";
         };
       };
     };
@@ -48,11 +52,11 @@
     start_all()
 
     machine.wait_for_unit("mediamtx.service")
+
     machine.wait_for_unit("rtmp-publish.service")
-    machine.sleep(10)
+    machine.wait_until_succeeds("curl http://localhost:9998/metrics | grep '^rtmp_conns.*state=\"publish\".*1$'")
+
     machine.wait_for_unit("rtmp-receive.service")
-    machine.wait_for_open_port(9998)
-    machine.succeed("curl http://localhost:9998/metrics | grep '^rtmp_conns.*state=\"publish\".*1$'")
-    machine.succeed("curl http://localhost:9998/metrics | grep '^rtmp_conns.*state=\"read\".*1$'")
+    machine.wait_until_succeeds("curl http://localhost:9998/metrics | grep '^rtmp_conns.*state=\"read\".*1$'")
   '';
 }
diff --git a/pkgs/by-name/me/mediamtx/package.nix b/pkgs/by-name/me/mediamtx/package.nix
index 5bd4506f7f75..ad98797bcc45 100644
--- a/pkgs/by-name/me/mediamtx/package.nix
+++ b/pkgs/by-name/me/mediamtx/package.nix
@@ -8,23 +8,23 @@
 
 let
   hlsJs = fetchurl {
-    url = "https://cdn.jsdelivr.net/npm/hls.js@v1.5.20/dist/hls.min.js";
-    hash = "sha256-0BbBIwSW7lnz9bAcFszkzAG1odPTV63sIAyQixMevkk=";
+    url = "https://cdn.jsdelivr.net/npm/hls.js@v1.6.2/dist/hls.min.js";
+    hash = "sha256-5lAT3DQ1tVo0tSV6fmWDWSbB9NVyCduomoENNQX08UM=";
   };
 in
 buildGoModule (finalAttrs: {
   pname = "mediamtx";
   # check for hls.js version updates in internal/servers/hls/hlsjsdownloader/VERSION
-  version = "1.12.2";
+  version = "1.12.3";
 
   src = fetchFromGitHub {
     owner = "bluenviron";
     repo = "mediamtx";
     tag = "v${finalAttrs.version}";
-    hash = "sha256-O3Iu9gvCiAVuoJw77MWPyCfuJVcw0E8YWcJBiJq+/Ms=";
+    hash = "sha256-2eTvRWFSR6sXnUJJPKvzQhSqbg1Unh8QuxmyixAw8Cc=";
   };
 
-  vendorHash = "sha256-0927IeFIC2rhApPVs5ZIvS3yoDN8Km3tHgrRXnP/wBc=";
+  vendorHash = "sha256-CdJS+RebJA6CpOo6YLlTpCXzE0eWSAnWzVXECvgMBvc=";
 
   postPatch = ''
     cp ${hlsJs} internal/servers/hls/hls.min.js