"Activity Light on All the time."

My Cable Modem has 5 lights.
One for Power
One for Receive
One for Send
One for Online
One for Activity

The power, receive, send, and online lights have been green and on since the beginning. Which is great. Now it seems for the first 36 hours I've have this service the Activity light only came on when I did something on the internet. (Note: I've only had the service about 48 hours) Now it would seem the activity light is blinking no matter what I do, even nothing. I rebooted the PC and as soon as it had power back the light started blinking? I called their phone support and they said that was normal and everything with my PC looked fine. So my question is this: Does anyone else's activity light just blink all the time? Thanks

You don't say what brand of modem, but most likely the always blinking activity light is showing traffic from your modem to the ethernet card. Why not check out the manufacturer's web page for a technical explanation of what each light measures. By the way, the always blinking activity light would be normal; there is always activity between your modem and ethernet card.

This is a light on the front of the modem. I have also watched the lights on the back of the modem and my NIC. They seem to only blink when I do something on the net. The modem is a Surfborad 3100. The web site doesn't say to much?

The lights that seem to always stay on your cable
modem, means you have Block Sync, which means you
modem is ready to go anytime you want to get on the internet. If your lights are cycling (spinning
or flashing very fast) your modem has to re-sync
itself before you can get on the internet. It means you lost your connection temporarily.

Don't be fooled or mis-guided. This could be a serious hacker looking and transfering files from your system. The data lights should not be blinking unless you are transfering or receiving data from the internet.

I've got an identical situation. Just hooked up 2 weeks ago with a SB3100. What is confusing is that the activity light worked appropriately for the first week. Now it flickers continuously even with PC off.

Cable modems "talk" back to the cable plant constantly adjusting signal levels, and checking modem status. The blinking lights are normal in most cases. Check the manual that came with your cable modem. If it doesn't have one, check the manufacturs web site.

the only reason for the lights all to be on is if your pc is sending and recieving data.If when your pc is off it doesnt blink then thats whats happening.Different programs are always looking for aconnection to netto update or keep current info.Like ICQ AOL instant messenger or virus scanning software.Even Windows update is always looking for updates.

there are a couple of things that can be happening. if your cable co. does not permit servers they can and probably will port probe which will make your activity light flicker non stop but not for hours on end. also someone may have gotten or just by luck punched in your ip to a trace or ping program which will make your activity light blink.Or someone may be trying to read info off your computer. you should probably try to find yourself a fire wall program that will let you trace back whoever is talkin to your modem and then save and let your provider know what is goin on. ps alot of them especially the sales people dont know crap about their products or service but if you make a big enough stink you will probably get someone who knows what to do with the info.
I may be wrong but this is what i would do.