We use our own answering machine to screen calls. (It also gives us a message waiting indicator.)
When calls come in, the phone rings once, the machine quietly picks up. If they start to leave a message, we can screen it and either pick up or not. But when people hangup during the message, we now get a busy signal. Before we converted, we would get silence.
It's a bit annoying.
Are there any options to fix this?
I noticed the HT801 administration guide <https://documentation.grandstream.com/knowledge-base/ht80x-administration-guide/> mentions:
Disconnect Methods: Busy Tone, Polarity Reversal/Wink, Loop Current