VOIP

I am experiencing a lag and sometimes echo in my phone conversations. I subscribe to the COX Preferred package. The speed test results are 56.09Mbs down and 9.33Mbs up. I am using a Cisco DPC3010 connected to a Linksys EA3500 router.  I have a Ooma Telo connected to the router. I have attached the info from the status page of the modem. Is there anything I can do to get rid of this lag and echo?

Model:     Cisco DPC3010
Vendor:     Cisco
Hardware Revision:     1.0
MAC Address:     
Bootloader Revision:     2.3.0_R1
Current Software Revision:     d3000-v302r125533-120716a-COX
Firmware Name:     d3000-v302r125533-120716a-COX.bin
Firmware Build Time:     Jul 16 17:16:46 2012
Cable Modem Status:     Operational
           
Cable Modem State      
        
DOCSIS Downstream Scanning:     Completed
DOCSIS Ranging:     Completed
DOCSIS DHCP:     Completed
DOCSIS TFTP:     Completed
DOCSIS Data Reg Complete:     Completed
DOCSIS Privacy:     Enabled
          
Downstream Channels      
        
                        Power Level:     Signal to Noise Ratio:
Channel 1:     -16.6 dBmV     34.0 dB
Channel 2:     -17.3 dBmV     33.3 dB
Channel 3:     -17.9 dBmV     32.4 dB
Channel 4:     -17.7 dBmV     32.6 dB
Channel 5:     -16.9 dBmV     33.5 dB
Channel 6:     -16.0 dBmV     34.1 dB
Channel 7:     -16.6 dBmV     33.4 dB
Channel 8:     -17.6 dBmV     32.8 dB
          
Upstream Channels      

                  Power Level:
Channel 1:     54.0 dBmV
Channel 2:     54.0 dBmV
Channel 3:     0.0 dBmV
Channel 4:     0.0 dBmV