diff --git a/lib/device.js b/lib/device.js
index 5967a7d..05b21a1 100644
--- a/lib/device.js
+++ b/lib/device.js
@@ -247,7 +247,7 @@ function set(deviceData, path, timestamp, attributes, toClear) {
         if (attrName in currentAttributes) {
           if (attributes[attrName][0] > currentAttributes[attrName][0]) {
             changeFlags |= CHANGE_FLAGS[attrName];
-            if (compareEquality(attributes[attrName][1], currentAttributes[attrName][1]))
+            if (!compareEquality(attributes[attrName][1], currentAttributes[attrName][1]))
               changeFlags |= CHANGE_FLAGS[attrName] << 1;
           }
           else