I couldn't find a direct download for 2877, and the default "latest" firmware download link provides 2872. Either it's sloppy release management on Obihai's part, or they deemed 2877 such a minor change that it wasn't worth the trouble. Maybe Obiahi Mark will see this and respond.
If you want to try to force the upgrade, you can do this:
Log onto your OBiTALK portal page. I assume you previously added your 110 to the portal. Make note of any settings customizations you may have made in the past, because this will erase them. Find the listing for your 110 device and delete it off of the portal. Wait a few minutes for the portal to send a reset command to your OBi.
Do a paper-clip 10-second factory reset on the OBi box, to be sure it is now in a "virgin" state. Now, click the "Add device" link on the portal, and perform the **5 procedure to have OBiTALK find and add it.
Now, log into one of your Google Voice accounts on another tab of the same web browser session. Go back to the ObiTALK portal page tab, and add GV as your desired service provider (SP1 or SP2, corresponding to the GV account you logged into). If you're lucky, OBiTALK will download and install the 2877 firmware as part of the Google Voice setup process. If it doesn't, then I wouldn't worry about it. Log into the other GV account and repeat the procedure to add it to the other SP slot.
