[ntp:questions] ntpd losing sync

[A C]

For reference, this is what the system looks like normally until the 
oscillations go out of control and wipe out clock sync:

       remote           refid      st t when poll reach   delay   offset 
  jitter

==============================================================================
  o127.127.22.0    .PPS.            0 l    2   32  377    0.000    0.005 
   0.061
   127.127.28.0    .GPSD.           4 l  115  128  377    0.000  -23.269 
   4.368
  -74.118.152.85   69.36.224.15     2 u  456  512  377   42.365    0.631 
   0.334
  +68.0.14.76      .GPS.            1 u   69  512  377   79.443    2.383 
   0.249
  +173.203.122.111 209.51.161.238   2 u   67  512  377   74.682    1.053 
   0.361
  *130.207.165.28  130.207.244.240  2 u  232  512  377   94.749   -4.766 
   0.619
  -131.144.4.10    130.207.244.240  2 u  404  512  377   84.795    2.599 
   0.804