You maybe have another idea ?
vro:~ # ntptrace
localhost: stratum 16, offset 0.000000, synch distance 0.437160
vro:~ # ntpq -p
remote refid st t when poll reach delay offset jitter
==============================================================================
nwld-ad1.nwld.l .LOCL. 1 u 17 64 377 0.604 -16971. 0.568
nwld-ad2.nwld.l 10.0.2.30 2 u 25 64 377 1.909 -16972. 5.582