I love VM support (sarcasm!)... so the guy says its in modem mode and I need to disconnect my other equipment (not just switch modem mode off)
he does a test and says the lights are all green, so its the hub at fault because its old and discontinued - no reason as to why it would suddenly have an attenuation problem.
I ask him how it will fix the attenuation problem and he says, its because the hub is old!!!! (we run around in circles on this one)
So I say, fine send me a new hub... what happens then? Are you going to say what the next step is when this makes no difference...
again, its the hub which is your problem. !!!!
The guy didnt have a clue how a network works, what attenuation is, what causes problem, what happens in the cabinet. He is just following the script.
So they are sending me a new hub - sorry Comcast, i dont need it and didnt want to eat into your profits... its a totally unncessessary expence... and I know I'll be calling back next week for an engineer to come and visit to check why the attenuation is wrong.
Attenuators are used to reduce distortion caused by the voltage being too high, just like when a volume control is up too high on audio equipment the sound goes into clipping and distortion. When the Broadband signal is distorted it becomes harder to read by the Hub and IP distribution equipment.
i checked this morning and Im getting better performance close to max but still below on the downstream side (see how that goes today!)
I had a 10dB attenuator laying around (dont ask!) so I tried that and it made no difference. Signal was still being read at same strengh which I thought was odd! but also made no difference to the throughput.
I am now curious how the hubs read signal strength and on what cadence... is it instantanious or what? I did powercycle the hub in between adding the attenuation in case it was prompted by the powercycle.
I am going to assume an engineer is required to check the signal and prob make a tweak at the cabinate.