Razer Viper Ultimate - erratic cursor when using dongle

My mouse has worked perfectly for years, then today it started being erratic with cursor movement and also needs a longer click for it to register on the PC.

If I plug the mouse in directly using the docking cable, all is good.

Battery is 78%, I reloaded the Synapse drivers from scratch.

Mouse acts the same on my laptop.

Can the dongle go bad, but still partially function??

Any suggestions are appreciated.

Thanks