Since yesterday afternoon our internet and TV services have both been out. The modem's US/DS light is blinking and the online light is off, and the tv box just says "cast." I tried unplugging and rebooting the tv box and modem twice each, and also tried different coax cables in different locations in the house but ended up with the same results. Can anyone shed some light on what the problem may be here, and if this is something a tech needs to investigate? Thanks in advance!
First, check for general local area outages;
Please post the *Downstream Power Level*, the *Upstream Power Level*, and the *SNR* (Signal to Noise Ratio) numbers. Be advised that if you don't have a connection / synch with the system, you may not be able to get the signal stats. And even if you can get them, they may be meaningless / not accurate.
What is the exact make and model number of the modem ?
Yep. Not helpful. Try things here from my tips if you haven't before if they even apply. If not, get a tech out to investigate;
In a self troubleshooting effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test
If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.
Good luck !