RAXE500 suddenly got SUPER slow

So, last thursday our RAXE500 ground to a halt.  Some stuff worked.  my email server still worked, some of my instant messengers worked, but the web would simply time out.  then, the web came back a bit.  I could browse to speedtest.net, but clicking on test would take a full 2 minutes to even load the dial.  Once the dial loaded we were getting 50mb/s.  

I ran a ping test from the command line..

PING 8.8.8.8 (8.8.8.8): 56 data bytes
Request timeout for icmp_seq 0
Request timeout for icmp_seq 1
Request timeout for icmp_seq 2
Request timeout for icmp_seq 3
Request timeout for icmp_seq 4
Request timeout for icmp_seq 5
64 bytes from 8.8.8.8: icmp_seq=2 ttl=116 time=4805.434 ms
64 bytes from 8.8.8.8: icmp_seq=3 ttl=116 time=4867.189 ms
64 bytes from 8.8.8.8: icmp_seq=4 ttl=116 time=4750.193 ms
Request timeout for icmp_seq 9
Request timeout for icmp_seq 10
Request timeout for icmp_seq 11
64 bytes from 8.8.8.8: icmp_seq=8 ttl=116 time=4774.837 ms
64 bytes from 8.8.8.8: icmp_seq=9 ttl=116 time=4896.792 ms
Request timeout for icmp_seq 14
64 bytes from 8.8.8.8: icmp_seq=10 ttl=116 time=5058.307 ms
64 bytes from 8.8.8.8: icmp_seq=11 ttl=116 time=4804.332 ms
64 bytes from 8.8.8.8: icmp_seq=13 ttl=116 time=4802.473 ms
64 bytes from 8.8.8.8: icmp_seq=14 ttl=116 time=4697.538 ms
64 bytes from 8.8.8.8: icmp_seq=15 ttl=116 time=4542.406 ms
64 bytes from 8.8.8.8: icmp_seq=16 ttl=116 time=4788.158 ms
64 bytes from 8.8.8.8: icmp_seq=17 ttl=116 time=4801.874 ms
64 bytes from 8.8.8.8: icmp_seq=18 ttl=116 time=4688.956 ms

Steps I tried:

• factory reset the router (1.0.7.68), rebuilt settings from scratch

• Regress to 1.0.6.64 - same sluggishness

• Regress to 1.0.5.62, same sluggishness, not as bad

• regress to 1.0.1.52, Better, but still sluggish

• regress to 1.0.0.48 (origional firmware) problem gone.

                        64 bytes from 8.8.8.8: icmp_seq=2 ttl=116 time=21.307 ms

• after verifying everything was working as expected, updated to 1 version prior to current.  Problem came back.  Problem was solved by regressing again to origional firmware.

I know that our ISP is upgrading their equipment (fixed wireless) and changed us over to a newer accesspoint on the tower and unlocked the speed on our account.  For about a week we were getting upward of 80mb/s then it go to where we were getting socket errors for downloads on speedtest, latency errors and 60%+ packet loss.  I would open a web page and would have to wait almost 2 minutes before it would even start to load.