I think it's some sort of problem with my HM. Seems like some sort of grounding issue. I can't figure it out. I have other thermoworks products and the probes work good.
That still doesn't sound right, as you should likely be seeing massive issues across the board with all probes, were it a grounding problem. Simply put,
Thermoworks probes are pretty much THE best non-Thermocouple probes you can get for the HM. The problems you descibed that you say your Maverick doesnt have --- I think 99% of us have the opposite experience, in that the Mav probes fluctuate constantly and the Tworks are dialed in.
1. What version HeaterMeter board do you have?
2. What specific Tworks probes are you using?
3. Are you seeing noise on the probe lines? A small yellow or red "electrical" icon will appear next to the temp readouts on the main LinkMeter page with graphs. What are those noise values, if any?
I had the same issue previously. I purchased 2 probes, and 1 was bad out of the box. Readings would climb to 500, then cut off, then go to temp, then fluctuate rapidly between temp and 800 degrees. The one that works is awesome, though. Built very well and has a quick response time. I guess the bad one just got by QA somehow.
You say they would climb to 500.............................due to the temp actually being that? The probes have a max temp and 500F is it (aside from the high-temp air probe which can take 700F). Above those limits, the cabling starts melting from the inside and you're screwed.
In reality it sounds like a bad probe, but can easily be confirmed by comparing to a 2nd Tworks probe, assuming you have one. Temp probes are one of the most fail-prone electronics out there, and there's not much manufacturers can do to stop it.