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I have internet plus phone from Cox; I'm currently on the 150MB plan. I'd like to upgrade the internet, which requires a new modem. I don't want a combo/router unit; I have my own router setup and no reason to change it. The TM3402 modem would seem to suit the bill, but it seems to be unobtainable. I've tried both online chat and calling the nearest store; both told me that the panoramic gateway combo modem is my only option. Has anyone had any luck getting this modem from Cox?
Buy your own modem and keep the older modem connected for telephone service.
That's a possibility, but then I have to hook up a splitter. I think that I would do that rather than pay Cox $12/month for a modem that I hear isn't very good, though.
You're correct about the splitter but if you currently have no splitter...you're in a much better situation.
I have the TM3402 and its DOCSIS conked out last week. I had to connect an older DOCSIS and the conked-out TM3402 because its telephone side still works. However, to connect 2 devices, I had to replace my 2-way splitter with a 3-way. More splits...more degradation.
However, you have no splitter so you won't have as much degradation with the 2-way solution.
Just make sure to connect your Internet modem to the lesser leg of the splitter (3.5 dB).
...or you can just wait for the Solution Store to stock the TM3402. What's the hurry?
No one told me that they were out of stock at the moment. Both the online chat and the store at least implied that there was one option period.
Well, it's not the only option. Cox is just trying to push rentals.
only docsis 3.1 emta option that cox supports/carries
Correct. All Cox Voice devices appear to be D3.1. OP wants a D3.1 but Cox wants to rent it.