Tighten DIN connector?

[Gone Snorkelin']

I had the same problem. I contacted Tunze and they told me to pull back the black plastic/rubber connector cover to allow the plug to penetrate deeper. I tried it and it worked but my connector cover was now loose. I ended up trimming the black connector cover with a utility knife. I took off almost 1/8th of an inch and it has worked perfectly ever since.
Mike