Grandstream HT486

Usually these ATAs are set in router mode so you should be able to get into them easily.
  1. To access the interface go here:
  2. Next you need to type in “admin” and press enter .
  3. Click on Advanced Settings.
    1. SIP Server:
    2. SIP User ID: Enter your SIP ID Authenticate Password: Enter your VoIP Password
  4. Next we scroll down to “Register Expiration” set it to 600 seconds.
  5. Now we scroll down to “Enable Call Features”
    1. “Enable Call Features”: must be set to Yes
    2. Send DTMF: set to via RTP (RFC2833) and remove in-audio
  6. Set Reply to ICMP on WAN port to YES
  7. Set WAN Side HTTP Access  to YES
  8. Now go all the way to the bottom and click Update.