Time skips ahead by five minutes whenever a call comes in

Since there's no option to turn off "set time and date off CID" than all you can do is tell your provider that the time sent is incorrect. Doubt it will do any good but that's the only option. 

Given the searching I've done for this issue, and noticed that many others have said the same, I'm not surprised. I was hoping there just might be another way I hadn't found, but oh well. What I have done to test something is reset it, but I purposely set it wrong, so I'm hoping that, in theory, it'll be set to the right time when there's another call. 😂🤷‍♀️ 

Thanks for the reply! Much appreciated!

Unfortunately that won't fix it because it's still going to set the time to what the carrier is piggy backing on the CID's FSK signal.

The carrier is my cable company, so I guess I'll have to contact them, then. Thanks for letting me know, though!

As spoom2 says, that "5-minute off" time is being provided by your telephony provider when the call arrives.  You have every right to tell them that they're sending a bad time in the caller ID information and you'd like them to fix that.  My VOIP provider (Ooma) sets my phone's time correctly.

Once upon a time, I had an issue with my cell phone's clock being almost 2 minutes off.  After living with it for 3 weeks I complained to Verizon.  They actually fixed it pretty quickly after that.  I've had them send a time that's off by an hour before.