A factory reset doesn't affect the FW on Kindles

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Unless you have a full original matching image backup, you're fairly screwed, as Kubrick doesn't support the DX.
You're pretty much forced into going into even crazier territory, which'd be upgrading to 3.4.2, which I'm not sure anyone ever did, because the whole 3.x on a DX thing was a fairly terrible idea to begin with for roughly 99% of the population

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But to answer your question: yes, the outdated FW is why most SSL adjacent services are broken.