So I tried removing the clear silicone insert in the CU. It was still making the noise.Mine has a unique sound to it, I think it is the sound of the turbulent airflow but I don’t hear anything physically moving around like loose balls or anything
The CU makes the noise even when not connected to the device.
I tried putting the WPA on, and just drawing on it like it was a MP and no noises made. Resistance is massively improved also. Vapour was shockingly comfortable doing this.
If only some of us have this weird sounding CU, then it could be a fault. As I get really poor clouds with my CU compared with WPA. There is so much resistance that is caused by whatever the hell is making that noise.