New Tankless water system

We just took our maiden voyage in our Wildcat 282RK. All went well until my wife took a shower,the Girard water heater cycled on and off,going from scalding hot to cold. Called support and they said the low flow shower head was the cause.Did they not think of this before the new Wildcats were produced? Has anyone else had this problem with the new water heater?
Yes we can put a higher flow shower head on and this will fix the problem,but then you fill up your grey water tank faster.
I was told I was the first to call about the problem

Thanks , Roscoe L.

Well.......I hate to tell you, but they "lied" just like our POTUS.....this has been an ongoing discussion here on the forum.... just search for it and there will be multitudes... I must say.....I did go with the Oxygentics wand, which is a water saver also, and it pretty much did the trick for us.. Also, your incoming water pressure has alot to do with it also....if the pressure is under 45 pounds, it will cycle. If you do find your park water pressure that low, I would just run off the RV water tank/pump, as it seems to do the trick also...note: I always check the park pressure with a gauge before hooking up.....I ran into some parks this summer on our long trip and the pressure was just barely 20 lbs.....yet, also found a park, in St. Louis, MO that was 100 lbs....they warn you to use your regulator....sheesh, ya think so??