The program puts the time there by default. If it didn't you would be able to do so by adding something like the following to C:\Program Files (x86)\J River\Media Center 17\Skins\Theater View\[skin name]\main.xml.
<TEXT>
<Item Text="[Time]" Location="*\***" TextColor="808080" Rect="95,95,100,100" />
</TEXT>
The Rect= parameter defines the position and size of the rectangle the text appears in. If that's removed, it won't display anywhere. Also removing TextColor (now irrelevant), you have...
<TEXT>
<Item Text="[Time]" Location="*\***" />
</TEXT>
After modifying a skin like this, copy it to a new folder (i.e., the whold folder, like ..\Obsidian to ..\Obsidian (mod) so program updates don't overwrite your modification.