diff --git a/README.md b/README.md
index 3d2a600..4d8a661 100644
--- a/README.md
+++ b/README.md
@@ -32,6 +32,7 @@ A simple open-source web based [LXMF](https://github.com/markqvist/lxmf) client
 
 - Support for Audio Calls to other [Reticulum WebChat](https://github.com/liamcottle/reticulum-webchat) users.
   - Audio is encoded with [codec2](https://github.com/drowe67/codec2) to support low bandwidth links.
+  - Using a microphone requires using the web ui over localhost or https, due to [AudioWorklet](https://developer.mozilla.org/en-US/docs/Web/API/AudioWorklet) secure context.
 - Support for browsing pages, and downloading files hosted on Nomad Network Nodes.
 
 > NOTE: micron format parsing is still in development, some pages may not render or work correctly at all.