diff --git a/README.md b/README.md
index 691ca875..741ebd08 100644
--- a/README.md
+++ b/README.md
@@ -23,6 +23,9 @@ Documentation:
 
 ## Changelog
 
+### 0.0.2-alpha9 25.05.2020
+* (Black-Thunder) fixed crash when devices are assigned to different floors/areas
+
 ### 0.0.2-alpha8 25.05.2020
 * (Black-Thunder) fixed "Swing" of vanes
 
diff --git a/io-package.json b/io-package.json
index b308ef5e..ca47f046 100644
--- a/io-package.json
+++ b/io-package.json
@@ -1,7 +1,7 @@
 {
     "common": {
       "name": "melcloud",
-      "version": "0.0.2-alpha8",
+      "version": "0.0.2-alpha9",
       "news": {
         "0.0.2": {
           "en": "first implementation of device control, added more device options, extended and optimized logging (e.g. when logging into MelCloud), implemented polling of cloud data",
diff --git a/lib/melcloudPlatform.js b/lib/melcloudPlatform.js
index 6bf4d716..961bd9f7 100644
--- a/lib/melcloudPlatform.js
+++ b/lib/melcloudPlatform.js
@@ -103,6 +103,7 @@ class MelcloudPlatform {
 				if (jsonObject == null) return;
 
 				const foundDevices = [];
+				gthat.deviceObjects.length = 0; // clear main array first before adding new devices
 
 				for (let b = 0; b < jsonObject.length; b++) {
 					const building = jsonObject[b];
@@ -131,8 +132,6 @@ class MelcloudPlatform {
 	}
 
 	CreateDevices(building, devices, foundDevices) {
-		gthat.deviceObjects.length = 0; // clear array first
-
 		for (let d = 0; d < devices.length; d++) {
 			const device = devices[d];
 			const newDevice = new MelCloudDevice.MelCloudDevice(gthat);
diff --git a/main.js b/main.js
index 647f9fd4..75ffa6c5 100644
--- a/main.js
+++ b/main.js
@@ -256,8 +256,10 @@ class Melcloud extends utils.Adapter {
 				});
 
 				if(device == null) {
-					this.log.debug("Failed to get device object. Known object ids:");
-					this.deviceObjects.forEach(obj => this.log.debug(obj.id));
+					let knownIds = "";
+					this.deviceObjects.forEach(obj => knownIds += obj.id + ", ");
+					this.log.error("Failed to get device object. Known object IDs: " + knownIds);
+					this.log.error("This should not happen - report this to the developer!");
 					return;
 				}
 				this.log.debug("Processing change for device object with id " + device.id + " (" + device.name + ")...");
diff --git a/package.json b/package.json
index 4feb7c5f..98cd249a 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "iobroker.melcloud",
-  "version": "0.0.2-alpha8",
+  "version": "0.0.2-alpha9",
   "description": "melcloud",
   "author": {
     "name": "BlackThunder",