When using the analogue PCI cards in the T300/T500, the FXO CLIP settings are taken from the configured provider profiles in the PBX. In case of the setting Netherlands, the FXO is changed to DTMF CLIP. The reason is that the largest provider in the Netherlands is using DTMF clip. But when connected to other providers, they often use the FSK CLIP. There is no possibility to change the DTMF CLIP to FSK using the web-interface of the device.
You can change this via SSH access.
How to change DTMF CLIP to FSK
First you need to connect to the system using SSH.
Change the file: /etc/asterisk/chan_dahdi.conf
To be sure that the file is not changed by the PBX with scripting, you can change the rights of the file with CHMOD to 555 (read & execute)