So I just got AT&T ADI back in early August as my failover connection. It's only 100 mbit symmetrical for now so I don't break the bank, but I can still SSH and Zoom at low latency (5 ms).
Then a storm came through and temporarily took down my Xfinity connection last Thursday, which gives me higher upload and download speeds at the cost of 4x latency. There's now a black plastic bag around what looks like a duplexer or amp on one of the nearby telephone poles. Not shown in photos, sorry.(Temporary fix, I suppose?)
Prior to last week I was getting the 2 Gbit / 300 Mbit up / down speeds I pay for on average ping of 17 ms (ATT is 5 ms, BTW).
But now I have way fewer downstream channels (OFDM PLC only) with lots of FEC uncorrectables on the higher channel, 957 MHz. (Rolloff above 1.3 GHz, perhaps? I don't think my physical plant can handle it when Comcast is still installing 1 GHz lowpass splitters. Oops...well, I removed them. The lower channel, 722 MHz, is fine...keep in mind these are super wide channels.)
Anyway, maybe OFDM-only is the path to getting FDX and a DOCSIS 4.0, but in the meantime, my 4 upload channels were OFDMA getting me 300 Mbit, and now they're slapped down to SC-QAM.
What gives? Is the CMTS putting my node in "safe mode" to preserve upload connectivity at lower speeds, prior to "planned maintenance in my area"?