Yes, you'll see that a lot, & yes you're correct, within Kodi clear data in settings>tv>general only gives you the option to clear data which will delete the entire channel & guide database (note that this will also clear any customised channel changes such as groups/hide channels etc) but for troubleshooting it's generally a good idea to use this option. In system>tv>guide, clearing data will delete the cached guide data. Those two options apply when you're using the PVR Client/Live TV feature.
When people refer to clearing the cache for the IPTV Stalker Video Addon they mean launching the Video Addon & highlighting their server (NFPS, Rocket or IPTV66), bringing up the context menu with their remote/mouse & choosing clear cache.
You're using an android box, so you can easily clear your Kodi cache by exiting Kodi altogether & going to your android box settings>other>more settings>apps>Kodi>clear cache (do NOT clear data). When you relaunch Kodi you'll get a 'preparing for first run message' but your addons & system settings will have been preserved (provided you didn't choose clear data) & just your cached data will have been deleted. You can also use the Maintenance Tool that comes with the Fusion Installer to clear cache within Kodi, but some users don't like using third party apps like that at all for various reasons.
