sorry that it took so long to respond.   I eliminated mine by editing a file in the MU-2 sound config file.  Though I may have found a easier way.   In your FSX Sound Folder there should be a folder titled "MT", open the folder and scroll to the "SND63" .wav file file.  If you replace it with a silent .wav file that should eliminate the beacon sound. silent .wav's can be found on the net for free. Back-up your original SND63 .wav just in case.   let me know if it works or you need more ass