diff --git a/src/com/motorola/araplox/AFE4400Thread.java b/src/com/motorola/araplox/AFE4400Thread.java
index ccc8309..3471953 100644
--- a/src/com/motorola/araplox/AFE4400Thread.java
+++ b/src/com/motorola/araplox/AFE4400Thread.java
@@ -30,6 +30,8 @@
     private static final int address = (0x50 >> 1);
     private static final String TAG = "araplox";
 
+    private static final String preferredI2cBus = "/dev/i2c-4";
+
     private Mlx90620Listener listener;
     private I2cManager i2c;
 
@@ -114,6 +116,12 @@
             return;
         }
         String bus = buses[0];
+        for (String b: buses) {
+            if (b.equals(preferredI2cBus)) {
+                bus = b;
+            }
+        }
+        Log.i(TAG, "[pulse ox app] Using I2C bus: " + bus);
 
         int nsecs = 0;
         while (nsecs > 0) {