diff --git a/packages/jspsych/src/modules/plugin-api/HardwareAPI.ts b/packages/jspsych/src/modules/plugin-api/HardwareAPI.ts
index ed4b1726..3929c83d 100644
--- a/packages/jspsych/src/modules/plugin-api/HardwareAPI.ts
+++ b/packages/jspsych/src/modules/plugin-api/HardwareAPI.ts
@@ -9,7 +9,7 @@ export class HardwareAPI {
     //it might be useful to open up a line of communication from the extension back to this page
     //script, again, this will have to pass through DOM events. For now speed is of no concern so I
     //will use jQuery
-    document.addEventListener("jspsych-activate", function (evt) {
+    document.addEventListener("jspsych-activate", (evt) => {
       this.hardwareConnected = true;
     });
   }
diff --git a/packages/jspsych/src/modules/plugin-api/MediaAPI.ts b/packages/jspsych/src/modules/plugin-api/MediaAPI.ts
index 9eb83d3e..47310bff 100644
--- a/packages/jspsych/src/modules/plugin-api/MediaAPI.ts
+++ b/packages/jspsych/src/modules/plugin-api/MediaAPI.ts
@@ -27,7 +27,7 @@ export class MediaAPI {
   }
 
   getAudioBuffer(audioID) {
-    return new Promise(function (resolve, reject) {
+    return new Promise((resolve, reject) => {
       // check whether audio file already preloaded
       if (
         typeof this.audio_buffers[audioID] == "undefined" ||