Modem quickly reboots after 13mins

Hi Guys iv got a sb4200i which keeps rebooting. I loose my connection on my ps3 and laptop. It always looses connection every 13-15mins.  here is my log:  1010011630537-InformationI503.0Cable Modem is OPERATIONAL 1010011630537-InformationF502.1Bridge Forwarding Enabled. 1010011630537-InformationF502.3Bridge Learning Enabled. 1010011630537-InformationB0.0Baseline Privacy 1010011630537-InformationI500.0Registration Completed 1010011630537-InformationI0.0REG-RSP Registration Response 1010011630537-InformationI0.0REG-REQ Registration Request 1010011630537-InformationD509.0Retrieved TFTP Config File SUCCESS 1010011630537-InformationD507.0Retrieved Time....... SUCCESS ************7-InformationD511.0Retrieved DHCP .......... SUCCESS************5-WarningD520.2DHCP Attempt# 1 BkOff: 5s Tot DSC:1 OFF:1 REQ:1 ACK:1************7-InformationD0.0DHCP CM Net Configuration download and Time of Day************7-InformationT500.0Acquired Upstream .......... SUCCESS************8-DebugT503.1Acquire US with status OK, powerLevel 49, tempSid 1108************8-DebugT505.0Acquired Upstream with status OK************7-InformationT501.0Acquired Downstream (330750000 Hz)........ SUCCESS************8-DebugT509.0Acquired DS with status OK, DS Freq 330750000, US Id 2************7-InformationI510.0*** BOOTING *** SB4200-0.4.4.5-SCM01-NOSH-2.021010011630277-InformationH501.1HFC: Shutting Upstream Down 1010011630272-AlertT507.0Received Async Error Range Failed 1010011623307-InformationI503.0Cable Modem is OPERATIONAL  i Know that the problem is "Received Async Error Range Failed " but how do i fix it?  my signal levels which i think are causing the problem are as follows:  DOWNSTREAM  Downstream ValueFrequency330750000 Hz Locked Signal to Noise Ratio36 dBQAM256 Network Access Control ObjectON Power Level-8 dBmV  UPSTREAM Upstream ValueChannel ID2Frequency25800000 Hz RangedRanging Service ID1108 Symbol Rate2.560 Msym/s Power Level49 dBmV  Any help would be great