diff --git a/VERSION.properties b/VERSION.properties
index 0c239cdf..6e74ebe8 100644
--- a/VERSION.properties
+++ b/VERSION.properties
@@ -1,2 +1,2 @@
-client.version=1.5.21
+client.version=1.5.22
 server.version=1.4.9
diff --git a/shine-UI/js/services/call-service.js b/shine-UI/js/services/call-service.js
index df2e154c..b25dedd0 100644
--- a/shine-UI/js/services/call-service.js
+++ b/shine-UI/js/services/call-service.js
@@ -1668,6 +1668,7 @@ async function ensurePeerConnection(call) {
       call.videoSender = sender;
       call.videoTransceiver = (pc.getTransceivers?.() || []).find((tr) => tr?.sender === sender) || null;
       bindVideoSenderStream(call, sender);
+      await applyVideoSenderEncodingProfile(sender, 'placeholder');
     } else {
       ensureReservedVideoTransceiver(call);
     }
@@ -2008,8 +2009,8 @@ function ensureBlackVideoTrack(call) {
     return existingTrack;
   }
   const canvas = document.createElement('canvas');
-  canvas.width = 640;
-  canvas.height = 360;
+  canvas.width = 160;
+  canvas.height = 90;
   const ctx = canvas.getContext('2d');
   if (!ctx || typeof canvas.captureStream !== 'function') {
     return null;
@@ -2025,6 +2026,32 @@ function ensureBlackVideoTrack(call) {
   return track;
 }
 
+async function applyVideoSenderEncodingProfile(sender, mode = 'camera') {
+  if (!sender || typeof sender.getParameters !== 'function' || typeof sender.setParameters !== 'function') {
+    return;
+  }
+  try {
+    const params = sender.getParameters() || {};
+    const encodings = Array.isArray(params.encodings) && params.encodings.length > 0
+      ? [...params.encodings]
+      : [{}];
+    const nextEncoding = { ...encodings[0] };
+    if (mode === 'placeholder') {
+      nextEncoding.maxBitrate = 12000;
+      nextEncoding.maxFramerate = 1;
+      nextEncoding.scaleResolutionDownBy = 1;
+      nextEncoding.active = true;
+    } else {
+      delete nextEncoding.maxBitrate;
+      delete nextEncoding.maxFramerate;
+      delete nextEncoding.scaleResolutionDownBy;
+      nextEncoding.active = true;
+    }
+    params.encodings = [nextEncoding];
+    await sender.setParameters(params);
+  } catch {}
+}
+
 async function disableCameraTrack(call) {
   const videoTrack = call?.localVideoTrack || null;
   if (videoTrack) {
@@ -2068,10 +2095,12 @@ async function applyCameraState(call) {
       await videoTransceiver.sender.replaceTrack(videoTrack);
       call.videoSender = videoTransceiver.sender;
       bindVideoSenderStream(call, videoTransceiver.sender);
+      await applyVideoSenderEncodingProfile(videoTransceiver.sender, 'camera');
     } else {
       const sender = pc.addTrack(videoTrack, call.localStream);
       call.videoSender = sender;
       bindVideoSenderStream(call, sender);
+      await applyVideoSenderEncodingProfile(sender, 'camera');
     }
     videoTrack.enabled = true;
   } else {
@@ -2096,6 +2125,7 @@ async function applyCameraState(call) {
       try { await videoTransceiver.sender.replaceTrack(blackTrack || null); } catch {}
       call.videoSender = videoTransceiver.sender;
       bindVideoSenderStream(call, videoTransceiver.sender);
+      await applyVideoSenderEncodingProfile(videoTransceiver.sender, 'placeholder');
     }
     await disableCameraTrack(call);
   }