diff --git a/app/src/main/AndroidManifest.xml b/app/src/main/AndroidManifest.xml
index 818c807..f60830c 100644
--- a/app/src/main/AndroidManifest.xml
+++ b/app/src/main/AndroidManifest.xml
@@ -3,7 +3,7 @@
     xmlns:tools="http://schemas.android.com/tools"
     package="uk.org.openseizuredetector"
     android:versionCode="92"
-    android:versionName="4.0.0h">
+    android:versionName="4.0.0i">
     <!-- android:allowBackup="false" -->
     <uses-permission android:name="android.permission.BLUETOOTH" />
     <uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
diff --git a/app/src/main/java/uk/org/openseizuredetector/SdDataSource.java b/app/src/main/java/uk/org/openseizuredetector/SdDataSource.java
index 2eac58e..793cc27 100644
--- a/app/src/main/java/uk/org/openseizuredetector/SdDataSource.java
+++ b/app/src/main/java/uk/org/openseizuredetector/SdDataSource.java
@@ -478,9 +478,12 @@ public abstract class SdDataSource {
      */
     private void alarmCheck() {
         boolean inAlarm;
-        Log.v(TAG, "alarmCheck()");
+        // Avoid potential divide by zero issue
+        if (mSdData.specPower == 0)
+            mSdData.specPower = 1;
+        Log.v(TAG, "alarmCheck() - roiPower="+mSdData.roiPower+" specPower="+ mSdData.specPower+" ratio="+10*mSdData.roiPower/ mSdData.specPower);
         // Is the current set of data representing an alarm state?
-        if ((mSdData.roiPower > mAlarmThresh) && (10 * (mSdData.roiPower / mSdData.specPower) > mAlarmRatioThresh)) {
+        if ((mSdData.roiPower > mAlarmThresh) && ((10 * mSdData.roiPower / mSdData.specPower) > mAlarmRatioThresh)) {
             inAlarm = true;
         } else {
             inAlarm = false;
@@ -510,7 +513,7 @@ public abstract class SdDataSource {
             }
         }
 
-        Log.v(TAG, "alarmCheck(): inAlarm=" + inAlarm + ", alarmState = " + mSdData.alarmState + " alarmCount=" + mAlarmCount + " mAlarmTime=" + mAlarmTime);
+        Log.v(TAG, "alarmCheck(): inAlarm=" + inAlarm + ", alarmState = " + mSdData.alarmState + " alarmCount=" + mAlarmCount + " mWarnTime=" + mWarnTime+ " mAlarmTime=" + mAlarmTime);
 
     }
 
diff --git a/app/src/main/java/uk/org/openseizuredetector/SdWebServer.java b/app/src/main/java/uk/org/openseizuredetector/SdWebServer.java
index 2b0e182..0b92614 100644
--- a/app/src/main/java/uk/org/openseizuredetector/SdWebServer.java
+++ b/app/src/main/java/uk/org/openseizuredetector/SdWebServer.java
@@ -202,7 +202,7 @@ public class SdWebServer extends NanoHTTPD {
                 } else {
                     Log.v(TAG, "WebServer.serve() - Unknown uri -" +
                             uri);
-                    answer = "{'msg' : 'Unknown URI: '}";
+                    answer = "{'msg' : 'Unknown URI: "+uri+"'}";
                 }
         }
         res = new NanoHTTPD.Response(answer);