Large downstream fluctuations and weak/non-existant upstream speed

For the last 2 days now I have been experiencing some weird connection behavior.  I have Extreme 105 service, but I am experiencing fluctuations in downstream speeds as low as 44Mb/s.  My upstream is almost non-existent.

Speed test results just now show that the down stream seems to be reasonable, but the upstream is 0.5ish.  http://stage.results.speedtest.comcast.net/result/568637304.png

I'll try and post more when I notice the downstream fall out.

Modem signals:

Downstream Bonding Channel Value Channel ID 121  122  123  124  Frequency 555000000 Hz  561000000 Hz  567000000 Hz  573000000 Hz  Signal to Noise Ratio 37 dB  38 dB  38 dB  38 dB  Downstream Modulation QAM256  QAM256  QAM256  QAM256  Power Level The Downstream Power Level reading is a snapshot taken at the time this page was requested. Please Reload/Refresh this Page for a new reading 0 dBmV   0 dBmV   0 dBmV   1 dBmV  

Any thoughts?

Sorry about formating, I cant upload a screen shot atm, and the "Paste from Word" button doesn't seem to exist.