@sh4rkk 

You may wish to check Ethernet cable you use to connect PS4 to Deco and PS4 networking settings. I have similar setup and it works.

This is what I have:

Deco mesh running in Access Point mode.

Slave Deco M5 connected to ISP router by 5 feet Ethernet cable. Just like in your case, it is not Main Deco and it is not connected through Main Deco.

Deco M5 runs on latest software I can get through Deco app: 1.5.3.

Windows Server which sits nearby ISP router and used to be connected to router directly - I unplugged its cable from ISP router and plugged it to second port of Satellite Deco. 

Everything works seamlessly. Windows Server gets gigabit connectivity, appears in Deco app and can be managed in it.

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You have Deco S4 and I have Deco M5, but they are similar TP-Link technology and should operate same way. 

Yours is PS4 and mine is Windows computer, but as long as your Ethernet cable is good and PS4 networking settings are right, there should not be difference.

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As an initial troubleshooting step, I would suggest connecting PS4 directly to ISP Router, with same Ethernet cable you used to connect PS4 to S4.

Also, googling "PS4 connected no Internet" might help to narrow the issue, too, and offer specific to PS4 troubleshooting steps.

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I am also assuming you checked in Deco app that this Satellite S4 of yours is in good health, and reports Ethernet backhaul. You also see devices connected to it wirelessly, in Deco app.

@Alexandre. 

Hello, thanks for the extensive reply.

I can confirm that the Ethernet cable is not the problem.

Upon initial testing, I tried setting up my S4's in Router Mode via Wifi Backhaul and then tried connecting my PS4 to the slave Deco via its Ethernet port. The PS4 receives internet with this setup.

However, as stated above, with AP mode, the PS4 does not receive internet. I would prefer AP mode just to maximize the internet speed throughout the house.

Here's a topology to make things clearer: 

Am I doing something wrong with the AP mode setup?

@sh4rkk 

Your AP mode setup looks perfect and should work. I suspect PS4 Ethernet misconfiguration or issues with Ethernet cables. First, we should eliminate Deco node as a culprit. With your setup, that would be easy to do.

Take Satellite Deco 2 to where your Smart TV is, and connect Smart TV with Ethernet cable through Deco 2. If Smart TV has Internet access in that configuration, there is nothing wrong with Deco 2 unit, hardware wise. Deco mesh also works as expected. 

After you removed Deco 2 from its regular location, replace it there with networking switch. See if PS4 can get Internet when it is connected with the same cables, but through unmanaged gigabit switch instead of Deco 2.

This is the topology to run these tests:

Other things to try.

1. Please check if PS4 is not accidentally blacklisted in Deco app. Because, blacklist is the only place where one can deny device access to the Internet, when Deco runs in Access Point mode. Verify that Blacklist in Deco app is empty, and if not - delete all entries, even if they seem irrelevant. Make it empty.

2. When PS4 connected by Ethernet cable but has no Internet - check if it still reports IP address. If it does, and IP address is in the range 192.168.68.*, that is the one it got when Deco was running in Router mode, and won't work when Deco is in Access Point mode.

@Alexandre. 
 

I'll report back the next day, can't afford to test and fix my network today.. it's a busy day! :)

Appreciate the help, thanks a lot!