It is my understanding that Grandstream VOIP devices have a setting to Disable Busy Tone on Remote Disconnect. Since I am using my landline phone system’s answering machine to take calls coming in on my Extend Home (Grandstream) device, it sure is annoying to hear that tone at the end of every message that every caller necessarily generates when they hang up, and it sure would be nice if Republic Wireless were to make that a setting that could be changed, say through an otherwise locked-down web interface, or maybe a setting in my Republic Wireless Account phone(s) list, under the phone being extended.
I don’t believe that feature is available for this particular Grandstream device.
Edit: I did find other similar configuration features, but I haven’t played around with them (I don’t have an Extend Home, but use the Grandstream devices for other VOIP services):
Loop Current Disconnect: No Yes
Play busy/reorder tone before Loop Current Disconnect: No Yes
Loop Current Disconnect Duration: (100 - 10000 milliseconds. Default 200 milliseconds)
As the Republic Wireless’s use of the Grandstream device is preconfigured, you may want to offer this to Republic as a suggestion. See Where Can I Leave Feedback or a Suggestion for Republic Wireless? – Republic Help