Music on Hold is not been recorded (MixMonitor)

Hello,

I am using Asterisk pure code, not FreePBX, Elastix, etc.
I am running Asterisk 14.6.2 hosted in a VPS.

I am having issues to record the MOH using MixMonitor(/root/recording/file-xx.wav).

I am using a Cisco SPA504G and Eyebeam (softphone).

On both sides I lam able to listen MOH but the MOH is only recorded on the receiver.

How do I know that? Because when I listen the .wav file using FLV Player in windows, I only can hear the MOH in one side.

What can be the problem here? I dont see problems in the CLI. The moh is only stopped when I un-hold the call.