OpenVPN causing slowdown for YouTube on Android only

[Joek]

I've recently started using pfsense on a computer with the following hardware:
N3160
8GB RAM
32GB msata hard drive
2x Intel NIC 1gigabit

I've set up TorGuard and it's working decently (75mbps with vpn, of my 200mbps without). I haven't had a chance to work in the speed yet.

My main issue right now is YouTube and Reddit (possibly other sites, but I haven't had a chance to do expensive testing yet) are loading extremely slowly on the associated apps and when accessed via chrome on Android. This issue only occurs when OpenVPN is used on my pfsense box. If I used the TorGuard app and connect to the exact same server, even while OpenVPN is running, the load problems disappear. If I turn off OpenVPN and use my regular internet with no OpenVPN, there is also no loading issues.

Could OpenVPN be blocking something that TorGuard for Android does not? I use UDP for both.

Let me know if more information if needed.

[Joek]

After playing around with way too many settings, I finally discovered the solution:

1. Go to System/Advanced/Networking
2. UNCHECK -> Allow IPv6 [  ] All IPv6 traffic will be blocked by the firewall unless this box is checked
3. REBOOT

If you don't reboot the changes won't go through for this setting.

I'm still shaky on most of this stuff, so I'll leave it to someone else to educate me and others why this worked.

P.S. To verify it was this setting I did the following:
1. Reboot pfsense + phone with Allow IPv6 setting CHECKED
2. Verify YouTube app is closed on phone (swipe it away)
3. Open YouTube app, and verify it's taking 10+ seconds to load the main page
4. Change the allow IPv6 setting to UNCHECKED
5. Reboot pfsense + phone
6. Repeat steps 2 and 3, except instead of 10+ seconds it should be a few seconds