Hello!
We have a SMCD3R-CCR in our business environment, and occasionally we've had the modem appear to hard lock. All of the lights are a steady green when this happens, none of them are flashing, like the link ports. When this occurs, the only way to bring the system back online is to physically power off / on the modem. If we aren't in the office, it appears that the modem will eventually connect again, however, it can take upwards of a half hour to do so. This tends to happen 2-4 times a month, which doesn't sound like a lot. However, when we are running a business environment, this can be a real pain.
We haven't made any changes to our end that we think would affect this, so we're unsure as to what could be the culprit. I wanted to post this on the forum before contacting Comcast Business via phone, in case anyone had any suggestions. Thanks!