A few weeks ago, I bought a Cherry eVolution Marlin wireless desktop (it's a wireless, notebook-like keyboard and a laser-mouse, which are both connected to the PC using one little USB-receiver). Last weekend, when I turned on the PC, I realized that keyboard and mouse didn't work anymore. Neither keypresses nor mouse movements got to the PC anymore. Looking at the USB-receiver, I saw the red LED flashing rapidly.
It just looks like keyboard and receiver got out of sync and have to be re-connected or re-synced, e.g. like pressing connect buttons. However, neither the receiver nor mouse or keyboard have any hidden buttons or switches to initiate a re-connect and synchronize them.
I couldn't find any information on the net relating this issue, so I called the support hotline and found out that a rapidly flashing red LED at the receiver does indeed indicate that devices are out-of-sync. A friendly support assistant told me a way how the devices can be connected again.
It's easy and worked immediately for me. I wonder why they didn't add some notes about it to the operating manual. 1. Connect the USB charging cable to the PC, but not yet to the mouse 1. Turn off the mouse 1. Press and hold the left, right and middle (wheel) mouse button 1. While holding these 3 buttons, plug the USB charging cable into the mouse 1. You can release the buttons now. The mouse wheel should light up orange continuously 1. Press the horizontal scrolling buttons to the left 1. The mouse wheel should rapidly flash green for a short time and turn back to the usual charging indicator (slow orange/green blinking) afterwards
The red flashing of the USB receiver should now have stopped and keyboard and mouse should work again.
I wonder, how often I'll have to do this in future. It seems to be a common problem, since the support assistant almost immediately knew what I was talking about when I mentioned the rapidly flashing red LED. However doing this every few weeks wouldn't be too annoying -- it still turns out to be a very good keyboard
If you had similar problems, feel free to drop a comment :)