DPI Function makes some Internet Sides loading extremly slow
I noticed (already a while ago) when I turn the DPI function of my gateway on some sides, such as the one from "Kärcher" or "Automobilwoche" take forever to load.. even when in the VLAN of the device were I try to access the site, no filtering is enabled.
I want to use the the DPI function as AD & Analytics blocker, the function works well just some websites such as the ones I named take forever to load.
Not sure maybe it is related to the MTU issue I found earlier on the ER8411? Since the thing with the sides load forever is a bit similar?
@Hank21 Yes other websites work absolutely fine. Just with the ads blocked when the filter list I created (with all analytic & advertising apps) is enabled.
Interesting, on my remote site (Gateway is the ER7412-M2), the issue exists as well.
That is all that happens, just a loading icon without something happening. As you can see Firefox displays TLS-Handshake with XXX will be established/ carried out. 
That is how my settings look (for both sides).
Even when I deselect all restrictions the issue still happens, nothing else is configured in between.
The PC is connected to the SG3428X-M2 (on the remote side directly to the Gateway) and the switch via SFP+ to the Gateway.
DNS is the Gateway, iPv6 is disabled.