I own a SB6121 and as of last my internet dropped out and came back in about 20 minutes; however, now the modem will not channel bond (only connected to one channel). I have accessed the status page and reset the modem to defaults. I called comcast support and was told that they have to send out a tech as a owned modem cannot be accessed remotely. It seems as if this might be some type of provissioning issue. Is there anything else I should try before having a tech come out? I have 50/10 service (getting 30/10 now).
Can you post a screenshot of the modem's signals? They may indicate a downstream problem (which would be the cause of the loss of bonding.) This may help you determine more confidently whether it's a signal problem or a modem problem
Copy from signal page
Downstream Bonding Channel Value Channel ID 11
Frequency 675000000 Hz
Signal to Noise Ratio 38 dB
Downstream Modulation QAM256
Power Level The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading 5 dBmV
Upstream Bonding Channel Value Channel ID 2
Frequency 29600000 Hz
Ranging Service ID 3
Symbol Rate 5.120 Msym/sec
Power Level 43 dBmV
Upstream Modulation  QPSK  64QAM
Ranging Status Success Signal Stats (Codewords)
Bonding Channel Value Channel ID 11
Total Unerrored Codewords 24450941
Total Correctable Codewords 11
Total Uncorrectable Codewords 653
Hello JoshuaN and welcome,
The only thing that you need to make sure is that you are getting the correct Customer Owned Modem (COM) modem 6121 boot file. If you can very this with a technical agent at 800-391-3000, option is technical, internet, then it is very possible that your COM SB6121 may have to be replaced. I recommend after you verify that you are receiving the correct boot file, contact SB6121 technical support to have them login to your modem and let you know if the hardware, firmware for channel bonding needs update or replacement.
Hope this helps you out.