A freezing DVR or pixilated picture is almost always a signal issue or drop-line issue and never a box issue. Customers, if you have had more than two box swaps within say six months and the issue persists, the problem is not the box.
You need to contact Spectrum for a signal and drop line test. They should check your drop line, main tap, and inside and outside wiring. Box swaps will not fix this. Get your signals and drop lines tested.
To prepare for this test, avoid resetting any boxes, modems, or routers for six hours prior to your service call. Equipment resets put the error codes back to zero, and the tech needs to see the error codes. When the tech comes out, tune to a station that pixilates the most and say to him "I have already had four boxes." And the problem keeps coming back. You need your signals and lines checked. The problems could be splitters, animal chews, a corroded tap. It may not even be in your drop line, it may be further down your node. It may be old wiring in the home that needs to be updated.
You can also call Spectrum and request signal monitoring on your equipment. I would recommend this for 60 days. Ask the tech for the case number and have him escalate this issue. Request that a note be made on your account for signal monitoring for 60 days.
A separate post for a separate issue, (To answer the OP's inquiry.)
Lots of problems with the Spectrum apps have been reported nationwide. Hopefully, this improves within the next week or close to that. DVR boxes require a 48 hour wait period to be used with apps to sync to them on new installs. Subscribers with Spectrum Voice, may need to allow up to 24 hours for Caller ID to show on TV.