Extremely slow GUI in NetFlow manager 12.2.00

Hello,
The GUI in NetFlow Manager 12.2.00 is extremely slow compare to older versions (10.2.5).
It takes at least 15s to show the data for an interface.

VM:

Linux: Linux version 3.10.0-514.6.1.el7.x86_64 ( builder@kbuilder.dev.cento
Release : 3.10.0-514.6.1.el7.x86_64
Version : #1 SMP Wed Jan 18 13:06:36 UTC 2017
cpuinfo: GenuineIntel Intel(R) Xeon(R) CPU E5-2630 v3 @ 2.40GHz
cpuinfo: Hz=2397.267 bogomips=4794.44
cpuinfo: ProcessorChips=1 PhyscalCores=4
cpuinfo: Hyperthreads =0 VirtualCPUs =4
# of CPUs: 4

Memory: 8GB (4.5GB free)
Router: 1
Interfaces: 2
Disks: SAS SSD

I can not see a high CPU usage on the server.

This slow GUI makes the product unusable.
The best (ans fastest GUI) was the old GUI used in 9.x.

Any ideas????

Bye
Rainer Tammer