Samsung ME21K7010DS microwave randomly beeps and shows 7 on panel (fire hazard?)

[somewhathandy]

We bought a new to us house and it came with a full complement of Samsung appliances (ugh). When we bought the house the fridge ice maker was missing.  Apparently it froze up and the previous homeowner just removed it.  So we had that repaired/replaced.  Seems to be working for the past week or so but I won't hold my breath.  A bigger concern I have now is that the microwave started beeping by itself last night.  It showed "7" on the panel like someone hit the 7 key to start cooking.  No one had touched it.  After some google searching I found this and a few other threads that make me wonder if the microwave will burn the house down while we're at work.

https://us.community.samsung.com/t5/Kitchen-and-Family-Hub/Over-the-range-microwave-oven-inputs-7-by-itself-and-prompts-to/m-p/119927#M4487

I see there's a service bulletin here on the site for this exact problem and of course I can't view it because I'm not a pro.  Calling a service tech to come and look at it but was wondering if anyone ran into this and if it's truly fixable.  Some say there's a new door with an additional grounding wire, some say they replaced the door/keypad and the problem returned a couple weeks later... 

If a "new" door isn't going to fix it and I have to worry about it running for 77:77 as one poster said they woke up to after the house filled with smoke... I'd rather just replace it.  Any insight?

[Vance R]

Sound like a stuck key on the user interface. Model number would be helpful.

[somewhathandy]

Model number is in the post title.