RD Session Host slows down program

Hi All,

I have a problem with a new installed RD Server.
The configuration is as following:

The RD is running on Hyper-V. (VM host is Server 2012 R2 std)
Server 2012 R2 Std
CPU: 4 cores
Mem: 8GB

On the server is a program installed that is using SolidDB v4.50.
The program it self is fast, however when I install RD Session Host the program slows down.
Logging into it takes about 20 seconds, without the RD Session Host it takes a second or 2-4.

The other programs as Word, Outlook (Basically the only programs that are being in use) are fast.

I have also tried to install a new VM, same setup as above and made a fresh installation.
Without the RD Session Host its fast, Session host installed and the program is slow.

Does anyone have a suggestion howto improve the speeds?

Thanks in advance,

Patrick