I stumbled upon this topic, because I had a similar problem. If I'm honest, your original problem has changed over the course of time, so I don't think my solution will be applicable anymore.
Having said that, I don't think there is any harm in trying and posting this solution. When I replaced my laser, my new laser had a small think plastic sticker on the bottom, which was supposed to isolate electricity (I'm guessing), so that it would not work with the sticker. By removing that I solved everything.
Like I said before, I don't think this solution will apply to you anymore. But who knows, stranger things have happened in this world and maybe somebody else will have use for this solution.