Frequent modem reboots -- T4 connectivity timeout

Saw a thread or two with similar issues, but didn't identify a solution as of yet. 

Has anybody had success resolving an issue like this on their end?  

Configuration:

• SurfBoard SB6120 (Docsis 3.0) on the XFinity Blast package.
• 100-200 ft run from the lot termination point to the modem (house, not apartment). 
• Fresh install (line was connected in February this year, problems have been ongoing for 4-6 weeks).

Symptoms:

• 3-10 times per week, the modem appears to lose link (all LEDs switch to unlit except for the power LED).
• Connectivity is lost for about 90-180 seconds before modem re-stablishes link.
• Sometimes, connectivity is lost several times within minutes of a previous event.

Modem logs from most recent event:

Time Priority Code Message
Jul 16 2014 19:15:52 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:15:44 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:13 6-Notice N/A Cable Modem Reboot due to T4 timeout ;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:54 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:54 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:53 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:43 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:43 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:43 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:34 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:34 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 19:14:33 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 16:22:20 5-Warning Z00.0 MIMO Event MIMO: Stored MIMO=-1 post cfg file MIMO=-1;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:40 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jan 01 1970 00:00:13 6-Notice N/A Cable Modem Reboot due to T4 timeout ;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:00:00:00:00:00;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 16:20:52 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 16:20:52 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 16:20:51 3-Critical R02.0 No Ranging Response received - T3 time-out;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 16:20:41 3-Critical R06.0 Unicast Maintenance Ranging attempted - No response - Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;
Jul 16 2014 16:20:41 3-Critical R03.0 Ranging Request Retries exhausted;CM-MAC=00:23:74:f6:85:ad;CMTS-MAC=00:1b:d5:fe:9a:76;CM-QOS=1.1;CM-VER=3.0;

Modem Signal after event: