Microphone drops on Meeting

[ARmeeting]

My microphone stops picking up audio partway through a meeting. Normally around the 3 to 4 hour mark. Stages I've noticed are:

1. Calls running normally, nobody has joined or left for a couple hours.

2. Video goes a little fuzzy.

3. Microphone stops transmitting audio to the other meeting participants.

4. Video corrects itself, camera continues working with clear video, microphone does not work still.

5. 1 person, doesn't matter who, joins or leaves the call and microphone starts working again.

I'm using a KanDao Meeting, Model WL0308.

If anyone has any suggestions for troubleshooting or has experienced the same issues I'd appreciate the help. Thanks.