Hi ,
I have Mikrotik point to point link with good throughput . This connection is interrupted several times in a hour and This log can be seen : disconnected,too many poll timeouts .
This problem seen in configure with N band . I don't have any problem when configure in A/G band .
By the way I need At least 100 Mbps throughput and i forced to use N band .
Please help me to resolve the problem .
information about configuration:

Band : N
Channel Width : 20MHz
nstreme : enable
Dual chain : enable
WDS : disable
TX power : default
Tx/Rx signal Strength : -58/-59

Please run the following command on both sides and write the results here

Thanks for your follow up
Ap side :

interface=wlan1 radio-name="TL21" mac-address=D4:CA:6D:36:7D:F8
ap=no wds=no bridge=yes rx-rate="54.0Mbps" tx-rate="78.0Mbps"
packets=620,841 bytes=73843,163364 frames=620,844 frame-bytes=71017,158661
hw-frames=1624,1145683 hw-frame-bytes=135737,52873361
tx-frames-timed-out=0 uptime=7m9s last-activity=0ms
signal-strength=-55dBm@6Mbps signal-to-noise=63dB
signal-strength-ch0=-62dBm signal-strength-ch1=-56dBm
tx-signal-strength-ch0=-61dBm tx-signal-strength-ch1=-56dBm tx-evm-ch0=20
tx-evm-ch1=22 strength-at-rates=-55dBm@6Mbps 0ms,-54dBm@9Mbps 6m40s900ms,-
54dBm@12Mbps 6m38s810ms,-56dBm@18Mbps 6m38s570ms,-
54dBm@24Mbps 6m37s310ms,-54dBm@36Mbps 11s210ms,-55dBm@48Mbps
16s480ms,-55dBm@54Mbps 530ms,-53dBm@HT20-0 6m57s870ms,-
54dBm@HT20-1 6m40s940ms,-54dBm@HT20-2 6m38s550ms,-55dBm@HT20-
3 38s570ms,-55dBm@HT20-4 1s30ms
tx-signal-strength=-55dBm tx-ccq=85% rx-ccq=98% p-throughput=29368
nstreme=yes framing-mode=none routeros-version="6.0"
last-ip=192.168.42.139 802.1x-port-enabled=yes
authentication-type=wpa2-psk encryption=aes-ccm group-encryption=aes-ccm
management-protection=yes compression=no wmm-enabled=yes

Station side :

0 interface=wlan1 radio-name="TL2" mac-address=00:0C:42:9F:21:E7
ap=yes wds=no bridge=yes rx-rate="78.0Mbps" tx-rate="54.0Mbps"
packets=509,625 bytes=127256,62794 frames=509,628 frame-bytes=124658,59391
hw-frames=782,421091 hw-frame-bytes=162743,19427272 tx-frames-timed-out=0
uptime=2m36s last-activity=0ms signal-strength=-54dBm@6Mbps
signal-to-noise=63dB signal-strength-ch0=-61dBm signal-strength-ch1=-55dBm
tx-signal-strength-ch0=-61dBm tx-signal-strength-ch1=-55dBm evm-ch0=22
evm-ch1=19 tx-evm-ch0=21 tx-evm-ch1=17
strength-at-rates=-54dBm@6Mbps 0ms,-53dBm@9Mbps 2m6s40ms,-54dBm@12Mbps
2m5s10ms,-54dBm@18Mbps 2m2s70ms,-54dBm@24Mbps 1m59s780ms,-
55dBm@36Mbps 1m56s220ms,-54dBm@48Mbps 1m51s410ms,-
56dBm@54Mbps 1m46s850ms,-53dBm@HT20-0 2m6s390ms,-58dBm@HT20-
1 2m6s60ms,-55dBm@HT20-2 2m1s560ms,-54dBm@HT20-3 1m54s460ms,-
56dBm@HT20-4 0ms
tx-signal-strength=-54dBm tx-ccq=110% rx-ccq=100% p-throughput=28189
nstreme=yes framing-mode=none routeros-version="6.0"
last-ip=192.168.42.140 802.1x-port-enabled=yes
authentication-type=wpa2-psk encryption=aes-ccm group-encryption=aes-ccm
management-protection=yes compression=no wmm-enabled=yes

When use bandwidth test this link working properly .

...you have a classic case of "nstreme is not compatible with 802.11n standard"... Search this forum... there are quite a few posts about this problem...
If you're forced to use the "n" standard, try NV2 instead of nstreme...

edit:
Check this: http://forum.mikrotik.com/viewtopic.php?f=7&t=72025

Thank you for your reply and help .
Problem solved . Link up with 160 Mbps Throughput non stop .

Thanks to all

Thank you for your reply and help .
Problem solved . Link up with 160 Mbps Throughput non stop .

Thanks to all

How did you solve the problem?

Probably switched to Nv2.
It has been noticed long ago that nstreme is troublesome with 802.11n...
As far as I now know from experience RoS 5.20 works, might say ok. 1w15d without "disconected, not pooled...."

I'm afraid even to try again new RoS and nstreame on 2*2 MIMO linx.

Now we have only one PtP on nstreme 2*2MIMO RoS 5.20.
I can't meet with Nv2 and his ping-s but... In an emergency dog eats flies !