Yes the issue has been resolved. We discovered a few inverters would flicker certain lights under certain loads (I only know of two such occurrences, out of the thousands of systems we have sent out). Essentially it had to be a perfect combination of load, light, etc. We found adding an extra capacitor fixed the problem (they all now have this extra capacitor, so there should be no more problems with this). We did not find this during our testing, because we always tested at high loads. Now we test for this, and tested 500 of our inverters without the extra capacitor, and found two with the issue, however we added the capacitor to all of them just to make sure.
One of the problems is this customer is in Canada, and we don't cover shipping for warranty work to and from any location outside of the continual US. We actually discourage anyone from buying one outside of the continual US because of this, but some people are willing to tank the risk. However we did send him a new power module (we paid shipping) without him returning the old one (because he was using it off-grid, and didn't want to loose power, or have to use his apex while he waited to ship it to us). He was supposed to return the old one when he got the new one, but now that we he has the new one we have lost contact with him, and he has not returned the old unit.
I guess that is what we get for trying to be helpful. From now on we will not be sending out new units until we have the old one.