Hi, I’m not familiar with remote control “model 91s”, but that seems normal, at least, Viboton model described in this article uses blue light that flashes initially during the pairing sequence with the receiver. Later on, blue LED flashes when you press the buttons. Not sure what is wrong with your model, but I guess it cannot pair with the receiver. Also, sometimes you have to restart PC, because for whatever reason (power surge for e.g.) the connection becomes lost, until reboot or manual eject/inject of the USB receiver.

No

It seems that this is a common problem with this model. I also experienced weird cursor movements bugs e.g. from top to bottom and staying there.

The only advice I can give you is to turn it on/off couple of times and perform reconnect and calibration function. Rotate it upside-down so that you face keyboard side (keep it parallel to the floor or just lay it down on a table), click Fn + Esc for a second or so and then wait until LED stops blinking. Take it in your hand and try if it works ok. You might need to repeat this couple of times.

If it doesn’t help, then it must be malfunctioning because of a different reason. Move it away from other wireless devices to avoid interference.

Also, hold OK for couple of seconds to disable air mouse feature, it will be enabled again when you cycle on/off switch. Maybe this will help.

I have switched to mini wireless keyboard, simply because it is more reliable in my case, but remote is definitely more convenient for a hand.