Agreed. Choose channel 1 for the first AP and 6 (or 11) for the second. Your problem will most likely be solved.

So if you have four Wi-Fi base stations, it's probably better to use channels 1-4-8-11 in North America rather than have two base stations sit on the same channel in the 1-6-11 configuration. In Europe and many other parts of the world 1-5-9-13 is possible, which provides the 20MHz separation needed for 802.11g and 802.11n
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In some cases, the best choice is to select the same channel your neighbors are using. That way, your network and theirs will politely take turns transmitting. Waiting for your neighbor's transmissions will reduce your maximum throughput, but they also wait for you, so you get to transmit at maximum speed when it's your turn. Alternatively, if you choose a channel that heavily overlaps with a neighbor's network that is both strong and active, the two networks won't "see" each other and rather than take turns, generate interference when they both transmit at the same time, reducing the usable transmission rates.