Philia_Bear How much weight on the drawbar?
With the p80 awd system you can put heavier rated springs into it but ride will suffer when not towing
^^
What he said.
From memory these things have a tow rating of 1600kg.
If it has a square hole hitch receiver towbar, then your max downball load is around 160kg (or less).
i.e. drawbar weight on the towball
From your picture you look like you have a fair bit of mass (load) forward of the trailer axle.
e.g. bikes, spare wheel, load box etc.
Too much ball load will cause this issue.
Whether you have HD springs or airbags or whatever, they don't magically 'remove' mass on the towball.
How do you check downball load?
Buy one of these from Repco/SuperCheap or
https://parksidetowbars.com.au/BALL-WEIGHT-SCALE/8510-ffa6fc5c-4283-4a71-94ef-db508d306604/
Or call into Parkside when you're in town and ask if they can measure your downball load
Or rig-up something funky with some heavy scales.
Full disclosure I work for the company that has a commercial interest in Parkside