Hello, SUPER newbie here. We purchased a used and "refurbished" tub from a reputable dealer in May of 2020. It worked great for a few months but then we heard a sort of "knocking" sound that happened once and then never happened again. Because this happened within our 6 month warranty window we let the dealer know. While the "knocking" sound never happened again, a few months later the tub began tripping the breaker. Long, long story short, we contacted the dealer and have tried everything under the sun to fix it. Nothing makes logical sense (to me anyway). First they said our filter was clogged - bought a brand new filter - still happened. Then they said try it without the filter - still happened. We then had a second certified electrician come and look at the work the first certified electrician did - found no issues. Sometimes it trips after running a few days - sometimes it trips right away. However, it's never tripped while we've been in the tub. I'm about ready to return it and be done with the whole thing! Thoughts?