Flakey connection

[#1]

Hi
Had a hanging connection so ran some tests:
Rate (Kbps):          3008  96

SNR Margin (dB): 13.4  6.0
Attenuation (dB):  57.0  31.0
Output Power (dBm): 11.1  18.6

Running diagnostics, sometimes they are all
green, sometimes 'ping isp default gateway' fails
sometimes just 'ping preferred DNS server' fails
and sometimes both of those fails.
After rebooting the modem:
SNR Margin (dB):  12.3  20.0
Attenuation (dB):         56.0  30.5
Output Power (dBm): 12.0  18.6
Can anybody see what the cause is looking at the stats? After rebooting the modem it seems to have settled down, just curious what happened, appreciate any thoughts on this. 

[#2]

You were connected to pcl-ag03 until 11.10 this morning which was affected by a problem as listed here. Please let us know if you see any further issues

[#3]

Thanks Ben, this seems to happen now and then and yes, rebooting my modem usually corrects it.