Try removing the key and cleaning and/or adjusting the grey contact.
To remove the keys push down on the back and pull forward.

If that doesn't fix it, its much more work, but you will need to
remove the keyboard assembly and check the screws and diodes. If
that doesn't work, you can remove the keyboard PCB and grey membrane
contact and clean both the PCB and contact strip with carbon contact
cleaner.

-Ben


--- In chromapolaris@yahoogroups.com, "edoplastico"
<edoplastic2003@...> wrote:

>
> I'm Edoardo Gennaro.
> When i received my polaris, the box was external, thery ugly, so i
> modified it.
> Also the Attack slider of filter envelope was not working, I had to

re-

> solder it onthe board.
> Now, the only thing that doesn't works is the E5 key tha plays only
> the maximum thelocity also if you press very soft.
> I don't know how resolve the problem.
> Anyone had the same problem?
> Edo
>
> PS
> Polaris has a great sound, is fantastic.
> A tweeter killer!
>