Multiple AP, same SSID co-location interference

Co-location interference or adjacent channel interference on your wifi - which is worse?

Currently I am dealing with an apartment situation with multiple APs with one SSID on one channel - which I get as channel 5 at -43dB signal. Problem is there is an adjacent business (very close to my unit) using channel 6 at -70dB.  The signal is strong yet cuts out/drops out constantly and crawls at dial-up speeds yet sometimes I can get 25Mbps on a bandwidth test. This happens regardless of device.

overlapping wifi ap channels in question,  showing adjacent channel interference

I think I am the only one with an issue because no one else is complaining and I can't imagine the apartment owner would invest this much money (recently installed with 4APs for only 8 units) in a fancy wifi network not to have it work right.


Now I know having one SSID with multiple access points on a single channel is no problem but what about other SSID's using the same frequency spectrum? I came across the below information, hinting that adjacent channel wifi interference is worse than co-channel interference.

From: Wifi Nigel: Adjacent Channel Interference:

For some reason, performance recovered quite a lot with a 10MHz spacing and dropped back off again with a 5MHz spacing.

Once we hit zero spacing (i.e. both APs on the same channel), things recovered, as both APs would both be playing nicely, effectively sharing the available RF bandwidth between them.

I'm not sure who to believe because other people say the opposite, such as here:

http://serverfault.com/questions/471721/adjacent-channel-versus-co-channel-interference

 "adjacent channel noise is easier to deal with than co-channel noise (frequency congestion)."

Your thoughts?

I might invest in a directional antenna but that would really mess up my laptop portability. Contacting hte landlord is out of the question, he isn't tech savy and I don't want my rent to go up with constant complaints. I might go ask the business next door to change to channel 11 though...

Thanks.