diff --git a/build.gradle b/build.gradle
index abc3373..3328f06 100644
--- a/build.gradle
+++ b/build.gradle
@@ -6,7 +6,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.3.2'
+        classpath 'com.android.tools.build:gradle:4.0.1'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
diff --git a/library/src/main/AndroidManifest.xml b/library/src/main/AndroidManifest.xml
index ca30e8d..dfe74c1 100644
--- a/library/src/main/AndroidManifest.xml
+++ b/library/src/main/AndroidManifest.xml
@@ -3,8 +3,7 @@
 
     <application android:allowBackup="true"
                  android:label="@string/app_name"
-                 android:supportsRtl="true"
-    >
+                 android:supportsRtl="true">
 
     </application>
 
diff --git a/library/src/main/java/net/ossrs/yasea/SrsEncoder.java b/library/src/main/java/net/ossrs/yasea/SrsEncoder.java
index bc47510..69a7075 100644
--- a/library/src/main/java/net/ossrs/yasea/SrsEncoder.java
+++ b/library/src/main/java/net/ossrs/yasea/SrsEncoder.java
@@ -34,7 +34,7 @@ public class SrsEncoder {
     public static int vOutHeight = 640;  // Since Y component is quadruple size as U and V component, the stride must be set as 32x
     public static int vBitrate = 1200 * 1024;  // 1200 kbps
     public static final int VFPS = 24;
-    public static final int VGOP = 48;
+    public static final int VGOP = 24;
     public static final int ASAMPLERATE = 44100;
     public static int aChannelConfig = AudioFormat.CHANNEL_IN_STEREO;
     public static final int ABITRATE = 64 * 1024;  // 64 kbps