Help With Hikvision API Requested

Is there anyone who has been trying to play around with the Hikvision API so far ?

Just for some more deep knowledge of the API's of the products I'm using I'm trying to get some to work with eachother. At the moment I'm trying to get an AXIS encoder to send an HTTP request to the Hikvision API once a certain Input is being activated so that the Hikvision moves to a certain Preset.

So far I've figured out I need to go to: http://<IP>/ISAPI/PTZCtrl/channels/1/presets/1/goto to get Preset 1 to activate. However, I keep running into the fact that I get the following statement:

<?xml version="1.0" encoding="UTF-8" ?>
-<ResponseStatus version="2.0" xmlns="">
<statusString>Invalid Operation</statusString>
The thing strikes me as weird tho, as I am using the correct credentials. I even tried using "username:password@ip" to see if that would work, but alas.
So, anyone have an idea what I'm doing wrong here ?
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