I can see this is also a ZTE.

Well, how old is your apartment by the way?

Well, since your apartment is over 20 years old, chances are the copper wire in your building itself is as old as your apartment, unless of course you have it changed before.

Check with your apartment management, who is responsible for the copper telephone wires in the entire building. From what I understand, it could very much the responsibility of the building management, NOT TM or TM's contractor. You need to verify who is responsible first as if it is not TM's responsibility, they will not check & replace it.

The firmware that supports IPv6 does NOT support UniFi at the moment.

For Wi-Fi 2.4GH channel, you should always only use Channels 1, 6 or 11.

each channel is 20MHz wide. There are all together 14 channels in 2.4GHz spectrum, & 2.4GHz definitely cannot have 14 non-overlapping 20MHz channels.

Basically only Channels 1, 6 & 11 are non-overlapping. So if you & your neighbor are both on Channel 6, the Wi-Fi protocol kicks in to ensure that everyone has a fair share of the bandwidth. However, if you set it to Channel 7, this overlaps with Channel 6 as well as 11. This will create an interference known as overlapping channel interference, which can be very severe in a place where there is a high number of access points.

This diagram perhaps explains:

Since your neighbor is using 13, then do NOT use 11, they overlap.

Using 6 is fine then.

You can still try Channel 1 besides 6. If the someone on Channel 1 the signal is weak, it would not be a problem for you.

The 40MHz channel width is used to achieve higher data rate (e.g. 300Mbps). It is actually using 2x 20MHz channels to achieve that, hence the 2+6 actually mean it is using a 20MHz channel 2 & a 20MHz channel 6.

Better to use 20MHz. 40MHz is known to cause some connectivity problems, especially if you have any Apple device.

That is actually characteristics of radio waves - the higher the frequency, the lesser the range.

If you are using Samsung Galaxy S4 (at least this is what I am using & discovered), do NOT hold the top half of the phone. Doing so will block Wi-Fi signals.

And if you are connected to the 5GHz band Wi-Fi, then take note the range of 5GHz is shorter, hence, if you are a little too far from your router, then the signals will also be affected.

I actually never been to this site but I just tried, well, no problem at all. Streams smoothly for me.

By the way, no point doing any traceroute as TM has blocked ICMP from the 3rd hop onwards, hence the timed out..

are you connected directly via cable, or Wi-Fi? I am suspecting it might be Wi-Fi problem.

Seems like possibly the UniFi in your area having issues? Do a speed test, what do you get?

Looks fine. My suspect could be due to routing issues, depending on which range of IP address you get. You may want to try to disconnect & reconnect with new IP range to see if it helps.

restart your router.

Hmm.. not sure then what could be the problem.

But in the case of YouTube... sometimes I do have bufferring, but at other times it works smoothly...

Don't forget the actual file server (or peers if you are on P2P file sharing) may actually have lower bandwidth available to you (some may actually do throttling)

So if you download only a single file from one single server, you may not actually max out the download bandwidth available, unless you are downloading a single file over multiple connections (such as in download manager software), or downloading multiple files from multiple servers.

One thing I noticed, the actual download speed from Microsoft Update servers is kinda slow.

In condo/apartment buildings, UniFi uses the existing phone wires without installing fiber straight into your home. Hence, no need, you apply directly through TM.

For your info, in buildings such as residential condos/apt, shopping malls, office towers, in most cases, it is "Fiber to the Building", then an equipment known as MSAN is installed at the telecommunications room to connect the fiber to, and from there, it's copper all the way to your premise.