Comcast XFINITY → [Equip] Password reset problems

This unit (SMC D3CM10604) came with the default password set. Unfortunately that username/password combination does not give access to the security settings. According to the manual (which didn't come with the unit) the username/password to allow access is MSO/changeme. This combination does not work on my unit. I tried the >15 second reset, but that didn't work. Anyone else have this problem?? I purchased this from Power & Telephone.

the "MSO" login is likely only available from the coaxial side of the gateway; it's intended for customer service reps from the cable company to login to the device. have you tried "admin/admin"? or "cusadmin/highspeed"?

Thanks, I'll give those a try. I can understand the cable company having some kind of access for updates. The user should be able to change the default password.