main, take some suggestions given by Android Studio.

app/src/main/java/com/hyperling/apps/infinitetimer/MainActivity.java

@@ -1,6 +1,5 @@
 package com.hyperling.apps.infinitetimer;
 
-import android.app.NotificationManager;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.content.SharedPreferences;
@@ -8,7 +7,6 @@ import android.graphics.Color;
 import android.media.AudioManager;
 import android.media.MediaPlayer;
 import android.media.Ringtone;
-import android.media.RingtoneManager;
 import android.net.Uri;
 import android.os.Build;
 import android.os.Bundle;
@@ -16,6 +14,7 @@ import android.os.Handler;
 import android.os.Looper;
 import android.os.Message;
 import android.provider.Settings;
+import android.support.annotation.NonNull;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
 import android.util.Log;
@@ -28,7 +27,6 @@ import android.widget.SeekBar;
 import android.widget.TableRow;
 import android.widget.TextView;
 
-import java.net.URI;
 import java.util.Map;
 
 public class MainActivity extends AppCompatActivity {
@@ -491,7 +489,7 @@ public class MainActivity extends AppCompatActivity {
 
     private final Handler incrementTime = new Handler(Looper.getMainLooper()){
         @Override
-        public void handleMessage(Message msg) {
+        public void handleMessage(@NonNull Message msg) {
             String tag = TAG + "handleMessage";
             if (DEBUG) Log.d(tag, "Starting");
 
@@ -537,6 +535,14 @@ public class MainActivity extends AppCompatActivity {
                 }
 
                 // Wait
+                Thread t = wait(tag);
+                t.start();
+            }
+            if (DEBUG) Log.d(tag, "Finished");
+        }
+
+        @NonNull
+        private Thread wait(String tag) {
             Runnable task = new Runnable() {
                 @Override
                 public void run() {
@@ -557,9 +563,7 @@ public class MainActivity extends AppCompatActivity {
                 }
             };
             Thread t = new Thread(task);
-                t.start();
+            return t;
-            }
-            if (DEBUG) Log.d(tag, "Finished");
         }
     };