I had that chirping sound on a brand new 2023 DK4720SE which developed at about 3hrs on the meter. I never got a response back from Kioti even after they promised to call me. I went to two Kioti service stations… clueless. The original dealer said they replaced an o ring which was causing a cavitation issue and claimed to have resolved the issue… but they didn’t Fix it. The noise in the steering hydraulics was still there. The dealer said they’d call me after contacting Kioti to get answers, but they too never called me back. They had even promised to replace the LEMON unit, but refused to do so when the time came. Instead, they offered a trade in value for a new unit. I wasn’t about to go through those issues again, so I opted to go the other Orange route. That Kioti unit was Chuck full of issues right out of the gate including leaks, chatter, etc.
I go so tired of their unreliable service and communication that I just traded it for a new Kubota L4802. Their dealers were 1, 2 and 3 hours away from me, with the primary dealer being 3hrs away. Such a waste of travel time, money and effort. Never again.
However, I wish you luck with your issue and do hope you can get it resolved. Several people on this forum have complained about these strange noises, but no one has provided a solution.