Schneider XW Pro and Modified Sine Wave Generators

A little update. Yes a 1500 watt heater, greatly dampened or fixed the issue. But.. while trying to figure out what/how the capacitors should be wired in. I purchased a costco $900. gen. Same issue. Except the heater trick doesn't work. There were big voltage spikes and fluctuations of VAR from -2583 to 1629 eventually the inverter knocked the new gen off line (as usual). New generator works perfect when bypassing the inverter. I THINK it might be the device operating state setting. On a generator that was not functioning correctly that state shows up as 'backup' and with a generator that worked properly (the older 6,800 costco special with a honda) the inverter setting shows "generator tie". It think that setting controls the tie method for the sinewaves. Something about it l extracted from Bing chat. ". It needs to synchronize the phase and frequency of the incoming AC signals to ensure they can be combined without causing interference..." I don't believe I can change that setting.
I was over my head before. My preference would be for Schneider to own up and have an engineer figure this out, but that's not going to happen. Does it seem like I am looking the right direction?

This is the new gen. Have no idea about what type of sine wave.

Firman 7500W Running / 9400W Peak Tri Fuel Generator​

Item 1300533

Model T07571

Update. Fixed the issue. No thanks to Schneider. In fact they still have no idea. Backed the firmware to v1.11 build 0049. Major bug in the latest firmware 1.19. Local energy store had same issues as me and came up with the firmware solution. Schneider needs to get on the ball before they burn someone's house down. During those voltage spikes, besides killing electronic equipment in the house the panel of the inverter was about 150 degrees f. No idea how hot it was internally. Please be clear, that firmware thing is a big deal. I don't recommend unless you have the SAME conditions as I. Even then, go through Schneider. Would hate to be the cause of some other electrical problems, since I am not an expert.