2 out of 3 interfaces stoped working

Hi all!

We have computer athlon 2200+, 2GB RAM, Mikrotik OS(v2.9.27) in the rack, with PCI to mini PCI card with 3 Wistron Neweb CM9 Wireles MiniPCI adapters - on it. Its connected to 3 sector antennas 16.7 dB.

wlan1 - works fine (20-22 clients like before)
wlan2 - works very bad (1-2 clients, with bad http, but good ping..used to have 18-20 clients)
wlan3 - doesnt work at all (used to have 15-17 clients)

We tried to replace CM9 card on wlan2 and wlan3 with no results. Connectors are dry. We havent tried to replace antennas.
Winbox → wireless tables → registration:
wlan1 - clients all there
wlan2 - only half
wlan3 - only 2

Anyone have a clue of whats wrong?

Happy New Year to all members!

upgrade and post your configuration
the gurus might see what is wrong and help you fix.
thanks