How to Improve WiFi Performance - Advanced Settings

I will looking for a tips for improve my WiFi Performance on GrooveA 52hp /a.
Here the current configuration:

/interface wireless
set [ find default-name=wlan1 ] antenna-gain=5 band=2ghz-b/g/n country=italy default-forwarding=no disabled=no distance=indoors frequency=auto frequency-mode=regulatory-domain hw-protection-mode=rts-cts hw-retries=6 max-station-count=30 mode=ap-bridge radio-name=“WiFi” ssid=“m4-WiFi” wireless-protocol=802.11 wmm-support=enabled wps-mode=disabled
Here the device status

/interface wireless> monitor wlan1
status: running-ap
channel: 2452/20/gn(15dBm)
wireless-protocol: 802.11
noise-floor: -95dBm
overall-tx-ccq: 94%

Actually my speed test (i know about interference) have some difficulty to reach 10mbps (on 30/30 hdsl) but with another device (PicoStation M2 or TPlink 741n) with the same configuration (Channel -Width - TX Power 20dbm EIRP) i reach a from 18 26 mbps…

Some one have some tips?

Use a sector antenna.

Sector Antenna? the device is at 4 meters from AP… And other AP works better without sector antenna…

print registration table please, it will show signals and more info

/interface wireless registration-table> print

INTERFACE RADIO-NAME MAC-ADDRESS AP SIGNAL-STRENGTH TX-RATE UPTIME

0 wlan1 10:66:75:F4:AD:BF no -41dBm@1Mbps 48Mbps 1h12m57s

tell me if you need more information

try this: preamble-mode=short

Nothing Changed instead Ping.
Ping is 1ms… the upload is 23mbps but download still with a not good rate (after a lot of test the max reached is 10mbps)

Mateo, is this happening with any client devices? or only one? If so, which device?

Can you open a New Terminal, and issue

/interface wireless spectral-history range=5ghz 0

and upload a screenshot here?

Now is in testing mode on my laboratory (tryng with Android - Notebook - iOS)

As request
/interface wireless band=2ghz-b/g/n
Groove5Ghz.PNG
/interface wireles band=5ghz-a/n
Groove2.4Ghz.PNG

Singal Client.PNG
Connection List.PNG
Traffic.PNG
Other Screen… Running 4 btest form desktop
1 udp tx
1 udp rx
1 udp tx rx
1 tcp tx rx

only one client connected

My Last Configuration

/interface wireless
set [ find default-name=wlan1 ] adaptive-noise-immunity=ap-and-client-mode antenna-gain=6 band=2ghz-b/g/n basic-rates-a/g=18Mbps,24Mbps,36Mbps,48Mbps,54Mbps
basic-rates-b=11Mbps country=italy disabled=no distance=indoors frequency=auto frequency-mode=regulatory-domain hw-protection-mode=rts-cts
keepalive-frames=disabled max-station-count=10 mode=ap-bridge multicast-buffering=disabled multicast-helper=full preamble-mode=short radio-name=TEST-WiFi
ssid=TEST-WiFi supported-rates-a/g=18Mbps,24Mbps,36Mbps,48Mbps,54Mbps supported-rates-b=11Mbps wireless-protocol=802.11 wmm-support=enabled wps-mode=
disabled

/interface wireless nstreme
set wlan1 enable-polling=no
/interface wireless
add mac-address=6E:3B:6B:3D:75:4C master-interface=wlan1 mode=ap-bridge name=wlan2 security-profile=profile ssid=“Second WIFI”
Groove Clients.PNG

I have a problem, which fits to this topic:
Usually I use on travels a D-Link DIR-505 (travel router) to connect to the hotel WiFi network (2.4 GHz) and connected to the DIR-505 a mAP as AP lite to spawn a local WLAN with direct VPN to the company network. This works in general fine, but awfully slow (max. 5-10 MBit/s throughput to the internet)
So I tried to replace the DIR-505 with a Mikrotik hAP (station mode), because I thought the bottle neck is the DIR-505, but no performance increase (still 5-10 MBit)
My latest idea was a hAP AC lite (2.4 and 5 GHZ radio) to connect to the hotel network with 2.4 in station mode and local AP with 5 GHz. (no change: still 5-10 MBit/s), Using 5 GHz to connecto the hotel (station) and 2.4 GHz as AP to connect to the local devices is even worse (2-3 MBit/s only).
Compared to connect the iPhone directly to the hotel network is around 50-60 MBit/s.

Setup:
(hotel network) — wifi → |(station 5.0 GHZ) - (NAT routing) - (AP with 2.4 GHz)| — wifi ----> local device eg. iPhone

In the company network the mikrotik AP deliver a performance of around 60 MBit/s, so the mikrotik routers are not the bottle neck (at least not in AP mode).

Can somebody explain, from where this huge performance loss is coming?