Activity Feeds are not updated (quick enough or at all)

As it looks like, the slowness of the site seems to affect the loading of the activity feed. I have been "investigating" with some tools (The Browser-Included F12-Diagnostic Tools), as well as Wireshark on my Desktop, along with some Network Diagnostic tools from the company I am working in on my Android Device.

The Problem is the following:

The Activity Feed will not update (quick enough or at all) when you go to someone elses Profile after visiting your own.

Steps to reproduce:

1. Go to your own Profile
2. Wait for everything to load
3. Open your Activity feed (The Bell on the top right) and directly go to someones profile (E.G click onto a person who recently followed you)

Expected Behaviour on all Devices:

The Activity Feed of that Person should be shown immediatly

Actual Behaviour on Desktopbrowsers:

Your own Activity feed is shown for a period of between 0.5Seconds up to 10 Seconds before it is replaced with the new one.

Environment:

Windows 7

150Mbps LAN Connection

Current Firefox, Opera, Chrome, IE11

Actual Behaviour on Andriod:

The Activity Feed will never be updated, altough Network Diagnostic Tools show me that packages are regularly sent to my device.

Environment:

Galaxy S7

150Mbps WiFi Connection

Firefox, Firefox Beta, Chrome, Opera, Opera Mobile, Samsungs Integrated Browser

EDIT:

I forgot to Mention that I am from Europe, maybe something fishy is going on here.