This has been a week of oddness...
Multiple sites with wifi, all have the same issue so far. High latency, ping time round trips of 3000ms plus, 70%+ packet loss, etc. Physical locations are spread from miles apart. Note that wired devices at these locations, even connected to the switch in the AP itself, work fine without issues and 38ms round trip times.
Location 1) Yesterday our Cisco AIR 1240 threw this fit... nothing would get it working correctly. Replaced with cheapo Linksys E2500 from Radio Shack... same issues. Upgraded firmware on 1240, wiped config, reconfigured and works like a champ.
Location 2) Today, separate physical location, WRT54GL loaded with DD-WRT has same issues. This is in a mill which is very dusty, and the AP has seen better days, so as I had to run into town anyways I picked up a cheapo Belkin N700... same issues with latency and packet loss.
Any ideas on just what is going on? Wirelessmon shows dropouts at roughly 1 per second. Signal strength typically around 50db. Location 2 is surrounded by nothing, not a single other AP and all channels are clear.