diff --git a/Yep/Info.plist b/Yep/Info.plist
index 4b0b23de..188fa3d8 100644
--- a/Yep/Info.plist
+++ b/Yep/Info.plist
@@ -19,7 +19,7 @@
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>
-	<string>50</string>
+	<string>51</string>
 	<key>Fabric</key>
 	<dict>
 		<key>APIKey</key>
diff --git a/Yep/ViewControllers/Conversation/ConversationViewController.swift b/Yep/ViewControllers/Conversation/ConversationViewController.swift
index 144a3dd0..513e33f0 100644
--- a/Yep/ViewControllers/Conversation/ConversationViewController.swift
+++ b/Yep/ViewControllers/Conversation/ConversationViewController.swift
@@ -2242,7 +2242,7 @@ extension ConversationViewController: PullToRefreshViewDelegate {
     
     func pulllToRefreshViewDidRefresh(pulllToRefreshView: PullToRefreshView) {
 
-        delay(0.7) {
+        delay(0.5) {
             pulllToRefreshView.endRefreshingAndDoFurtherAction() { [weak self] in
 
                 if let strongSelf = self {
diff --git a/Yep/Views/AudioWaves/Waver.swift b/Yep/Views/AudioWaves/Waver.swift
index d78b15e1..b0a70f8f 100644
--- a/Yep/Views/AudioWaves/Waver.swift
+++ b/Yep/Views/AudioWaves/Waver.swift
@@ -184,6 +184,10 @@ class Waver: UIView {
         
         println("Begin compress")
 
+        if waveSamples.count < 1 {
+            return nil
+        }
+        
         let sampleMax = maxElement(waveSamples)
 
         if sampleMax > 0 { // 防止除零错误