For the 320L NAS - DLink have already created a Universal Media Player that replaces Java
see my comment
http://forums.dlink.com/index.php?topic=62985.msg256522#msg256522and you can enable NPAPI in Chrome
Enabling NPAPI in Chrome Version 42 and later
As of Chrome Version 42, an additional configuration step is required to continue using NPAPI plugins.
In your URL bar, enter:
chrome://flags/#enable-npapi
Click the Enable link for the Enable NPAPI configuration option.
Click the Relaunch button that now appears at the bottom of the configuration page.
but if my memory serves me well Chrome will remove any NPAPI support on later version.