R7000P has no means of turning on/off its DLNA server

Hi.

In the admin page of the R7000P with Firmware Version V1.3.1.64_10.1.36, on the Advanced tab, under Advanced Setup, there is _one_ item under UPnP, and that is a checkbox [ ] Turn UPnP On, and un-checking it and choosing Apply _makes_no_difference_. On re-loading that page, the box is still checked, and in fact the DLNA server is still running.

====> I don't want to turn off access to the USB thumb drive altogether; I just want to turn off the DLNA server.

Please tell me what version of firmware I should upgrade/downgrade to, in order for _all_ of the admin pages to work correctly, and especially to be able to configure and/or turn on/off the DLNA server without disabling any other modes of access to USB device contents.

Thanks for any help.

Jim-Bob