diff --git a/hardware/blinkstick/76-blinkstick.js b/hardware/blinkstick/76-blinkstick.js
index bb78719c..0c1859f1 100644
--- a/hardware/blinkstick/76-blinkstick.js
+++ b/hardware/blinkstick/76-blinkstick.js
@@ -3,7 +3,7 @@ module.exports = function(RED) {
     "use strict";
     var blinkstick = require("blinkstick");
 
-    var availableModes = ["normal", "inverted", "neopixel"];
+    //var availableModes = ["normal", "inverted", "neopixel"];
     var availableTasks = ["set_color", "blink", "pulse", "morph"];
 
     Object.size = function(obj) {
diff --git a/io/emoncms/88-emoncms.js b/io/emoncms/88-emoncms.js
index e8e14b5f..bb3a24f4 100644
--- a/io/emoncms/88-emoncms.js
+++ b/io/emoncms/88-emoncms.js
@@ -65,8 +65,8 @@ module.exports = function(RED) {
             // setup the node group for URI. Must have a node group or exit
             var nodegroup = this.nodegroup || msg.nodegroup;
             if (typeof nodegroup === "undefined") {
-                node.error("ERROR: A Node group must be specified - " + nodegroup);
-                node.status({fill:"red",shape:"ring",text:"No Nodegroup"});
+                node.error("ERROR: the nodegroup is undefined");
+                node.status({fill:"red",shape:"ring",text:"No nodegroup"});
                 return;
             } else {
                 this.url += '&node=' + nodegroup;
diff --git a/io/mdns/mdns.js b/io/mdns/mdns.js
index 7482ebf3..b9e20f7d 100644
--- a/io/mdns/mdns.js
+++ b/io/mdns/mdns.js
@@ -58,7 +58,7 @@ module.exports = function(RED) {
         this.port = n.port;
         this.name = n.name;
         this.txt = n.txt;
-        if (this?.txt && (this.txt !== '')) {
+        if (typeof this.txt === "string" && this.txt !== '') {
             try { this.txt = JSON.parse('{'+this.txt+'}'); }
             catch (e) { delete this.txt; }
         }
diff --git a/io/stomp/18-stomp.js b/io/stomp/18-stomp.js
index 30ec6de1..063010f4 100644
--- a/io/stomp/18-stomp.js
+++ b/io/stomp/18-stomp.js
@@ -430,16 +430,15 @@ module.exports = function(RED) {
 
             node.on("input", function(msg, send, done) {
                 const topic = node.topic || msg.topic;
-                if (topic.length > 0 && msg.payload) {
+                if (typeof topic === "string" && topic.length > 0 && msg.payload) {
                     try {
                         msg.payload = JSON.stringify(msg.payload);
                     } catch {
                         msg.payload = `${msg.payload}`;
                     }
                     node.serverConnection.publish(topic, msg.payload, msg.headers || {});
-                } else if (!topic.length > 0) {
+                } else if (typeof topic === "string" && topic.length == 0) {
                     node.warn('No valid publish topic');
-
                 } else {
                     node.warn('Payload or topic is undefined/null')
                 }
@@ -479,9 +478,9 @@ module.exports = function(RED) {
 
             node.on("input", function(msg, send, done) {
                 const topic = node.topic || msg.topic;
-                if (topic.length > 0) {
+                if (typeof topic === "string" && topic.length > 0) {
                     node.serverConnection.ack(topic, msg.messageId, msg.transaction);
-                } else if (typeof topic !== "string") {
+                } else if (typeof topic === "string" && topic.length == 0) {
                     node.warn('No valid publish topic');
                 } else {
                     node.warn('Payload or topic is undefined/null')
diff --git a/parsers/base64/70-base64.js b/parsers/base64/70-base64.js
index b0cb98a4..a6e1790f 100644
--- a/parsers/base64/70-base64.js
+++ b/parsers/base64/70-base64.js
@@ -18,7 +18,7 @@ module.exports = function(RED) {
                 }
                 else if (node.action === "b64") {
                     if ( typeof value === "string") {
-                        var load = value.replace(/\s+/g,'');
+                        let load = value.replace(/\s+/g,'');
                         if (regexp.test(load) && (load.length % 4 === 0) ) {
                             value = Buffer.from(load,'base64').toString();
                             RED.util.setMessageProperty(msg,node.property,value);
@@ -37,7 +37,7 @@ module.exports = function(RED) {
                     }
                     else if (typeof value === "string") {
                         // Take base64 string and make into binary buffer
-                        var load = value.replace(/\s+/g,'');      // remove any whitespace
+                        let load = value.replace(/\s+/g,'');      // remove any whitespace
                         //var load = value.replace(/[\t\r\n\f]+/g,'');
                         //var load = value;
                         if ( regexp.test(load) && (load.length % 4 === 0) ) {
diff --git a/utility/annotate-image/annotate.js b/utility/annotate-image/annotate.js
index 3032594f..2d7532d1 100644
--- a/utility/annotate-image/annotate.js
+++ b/utility/annotate-image/annotate.js
@@ -93,7 +93,7 @@ module.exports = function(RED) {
                                             }
                                           }
                                           else if (annotation.labelLocation === "bottom") {
-                                            y = y + (10+h+(((defaultLineWidth*0.5)+(Number(defaultFontSize)))));
+                                            y = y + (10+h+((defaultLineWidth*0.5)+(Number(defaultFontSize))));
                                             ctx.textBaseline = "bottom";
 
                                           }
diff --git a/utility/exif/94-exif.js b/utility/exif/94-exif.js
index 7ea1c6f6..c290d697 100644
--- a/utility/exif/94-exif.js
+++ b/utility/exif/94-exif.js
@@ -2,11 +2,11 @@
 module.exports = function(RED) {
     "use strict";
 
-    function convertDegreesMinutesSecondsToDecimals(degrees, minutes, seconds) {
-        var result;
-        result = degrees + (minutes / 60) + (seconds / 3600);
-        return result;
-    }
+    // function convertDegreesMinutesSecondsToDecimals(degrees, minutes, seconds) {
+    //     var result;
+    //     result = degrees + (minutes / 60) + (seconds / 3600);
+    //     return result;
+    // }
 
     function ExifNode(n) {
         RED.nodes.createNode(this,n);