NTP does not sync

Hello,
i have a new SG330 for testing here, Firmware is up2date (9.355-1). But i have the Problem that the Time does not sync with the configured Time Servers. If i view the output of ntpq on the console i could see that the server never connects to the configured time-servers.
I also made a factory reset, but still the same.

If i use a time server from my local network, everything works.

any Ideas?

Output from ntpq -p on SG330
ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 LOCAL(0)        .LOCL.          10 l    -  128    0    0.000    0.000   0.000
 frank2.askja.de .INIT.          16 u    -  128    0    0.000    0.000   0.000
 dn3t.de         .INIT.          16 u    -  128    0    0.000    0.000   0.000
 gromit.nocabal. .INIT.          16 u    -  128    0    0.000    0.000   0.000

if i make the same configuration (firewall, nat, timeserver ...) on my utm home (9.370) everything works as expected:

ntpq -p from utm home edition:
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 LOCAL(0)        .LOCL.          10 l    -  128    0    0.000    0.000   0.000
+citadel.noetech 212.82.32.15     2 u   18   32  167   15.819   -0.436   1.746
*frank2.askja.de 130.149.17.8     2 u    -   32  377   15.873    0.406   0.858
+rs000486.fastro 192.53.103.108   2 u   29   32  377   15.473    0.722   0.719

Peter