AC-68U wifi decent, AX88U is pretty dire

[Nexy]

Quick explanation of topology setup:

Cable modem > AX88U > cat7 ethernet cable > AC68U

I have both routers set up on a fibre connection with 550 down / 35 up, the 68U being used just as an access point and a switch for devices near my PC. Please note: I disable/enable wifi on either of the routers, to specifically test them in isolation.

AC68U: Merlin 380.67
AX88U: Merlin 384.12

Ever since I got the AX88U, providing I have line of sight to the router, everything is perfectly fine, I can get ~350Mbps down, full 35 up, using my samsung S7 as a testing platform (yes, I know mobile phones aren't perfect for testing, but it's what I have available).

Now, if I go downstairs (or even on the same floor in the next room), with a single width brick wall in the way, bearing in mind my phone still says 4/5 bars signal, the throughput drops off dramatically on the AX.

AC68U: 262mpbs down 15.6mbps up. 116ms jitter

I do the exact same test, with both wireless configs set up identically - to the best of my knowledge (and bearing in mind at this point I disable the wifi on the AC68U, enable it on the AX88U)

AX88U: 4mbps down 0.91mbps up. 612ms jitter.

Both were in pretty much the same location (4 foot apart), testing with the same device, to the same speedtest server.

Configuration time:

AC68U:
Band: 5ghz
Enable Radio Yes
Set AP Isolated No
Roaming assistant Disable
Enable IGMP Snooping Disable
Multicast Rate(Mbps) Auto
AMPDU RTS Enable
RTS Threshold 2347
DTIM Interval 3
Beacon Interval 100
Enable TX Bursting Enable
Enable WMM APSD Enable
Optimize AMPDU aggregation Disable
Optimize ack suppression Disable
Airtime Fairness Disable
802.ac Beamforming Enable
Universal Beamforming Disable <This being on/off makes no notable difference.
TX power adjustment Performance

Wireless mode: Auto
Channel bandwidth: 80
Control channel: auto (plus Auto select channel including DFS channel checked
Extension channel: auto


AX88U
Enable Radio Yes
Enable wireless scheduler No
Set AP Isolated No
Roaming assistant Disable
Enable IGMP Snooping Disable
Multicast Rate(Mbps) Auto
AMPDU RTS Enable
RTS Threshold 2347
DTIM Interval 3
Beacon Interval 100
Enable TX Bursting Enable
Enable WMM Enable
Enable WMM No-Acknowledgement Disable
Enable WMM APSD Enable
Optimize AMPDU aggregation Disable
Modulation Scheme Up to MCS 9 (802.11ac)
Airtime Fairness Disable
Multi-User MIMO Enable
802.11ac Beamforming Enable
Universal Beamforming Disable < (Tried this enabled, makes no difference)
Tx power adjustment Performance

Smart connect: Disabled
Wireless mode: Auto
802.11ax HE frame support: Disable
Channel bandwidth 80 << (Tried 20/40/80 no difference)
Control channel: Auto (plus Auto select channel including DFS channel checked)
Extension channel: Auto


So, I "believe" that they're set up as close to each other as possible, with the AX having a few more options than the AC68U.

I am struggling to figure out why the AC68U performs so much better than the AX88U. It's a complete headscratcher at this point.

I've checked the antenna's and they're all on pretty tight too. If anything, the AX (in theory at least), should be better (miniscule) as it doesn't have to switch the traffic over the Lan to another device, to then be processed into wifi, but it's clearly not the case.

Wired connection off the back of the AC68U, I get ~520 down and 35 up (pretty much full advertised speed).

 

[Nexy]

The plot thickens. I borrowed my partners S9, and that had 229 down 35 up. So, oddly, it might actually be the phone that has issues. Tested with laptop downstairs, 350 down 35 up. So, I think I've nailed down where the issue lies. I'll do some more testing, but if it IS the phone, again, why does it like one AP but not the other.

 

[Grisu]

Why dont you update 68U to 384.12 too?

Delete Wifi-setting on client and connect again to AX88U, maybe better then.
Power off 68U in the meantime.

 

[barcote]

The plot thickens. I borrowed my partners S9, and that had 229 down 35 up. So, oddly, it might actually be the phone that has issues. Tested with laptop downstairs, 350 down 35 up. So, I think I've nailed down where the issue lies. I'll do some more testing, but if it IS the phone, again, why does it like one AP but not the other.

Have exactly the same problem. My wife's S7 has slowed to a crawl with the new AX88U. My S10 lightening fast and seems to play nicely with everything else - TV laptops etc. But the S7 3-4 mbps. The strange thing is that it can and does speed up to 40-50mbps often though not exclusively shortly after connecting but it soon reverts to 3-4mbps. Tried various different setting tweaks but to no avail. The damnedest thing...

 

[Grisu]

Have exactly the same problem. My wife's S7 has slowed to a crawl with the new AX88U. My S10 lightening fast and seems to play nicely with everything else - TV laptops etc. But the S7 3-4 mbps. The strange thing is that it can and does speed up to 40-50mbps often though not exclusively shortly after connecting but it soon reverts to 3-4mbps. Tried various different setting tweaks but to no avail. The damnedest thing...

Thats why I changed all Asus to AVM routers and now fast AND stable.

 

[Smokey613]

Thats why I changed all Asus to AVM routers and now fast AND stable.

Which model(s) of AVM did you go with?

 

[Grisu]

Which model(s) of AVM did you go with?

Thats OT here (3x7590 with 160MHz bandwith at 5G and a 7582 all used for <=150€ each).

 

[Val D.]

I am struggling to figure out why the AC68U performs so much better than the AX88U.

Are you sure both routers select the same control channel on Auto?
I would try locking both to the same 5GHz control channel an test again.