Qiu FAQ

Qiu FAQ (Frequently Asked Questions)

On this page you will find answers and tips to frequently asked questions that arise when using the Qiu (Qiu FAQ).

Please read the manuals that came with the Qiu carefully and also watch our Qiu instructional videos. You can find them here.

We generally point out that the settings of the Qiu, the degree of difficulty of the HRV biofeedback exercises, or their duration and the breathing recommended for training should only be changed with the consent of your supervising therapist or coach.

If you cannot find an answer to your problem or question on this page, it is best to send us an email to info@biosign.de with a brief description of your problem.


  • My Qiu just looks purple

    Your Qiu is in intensity-coded biofeedback (light/dark). This biofeedback mode is intended for people with red/green visual impairment. To switch back to red/green coded biofeedback you will need to reconfigure the brightness settings. You have two options for this:

  • My Qiu cannot be connected to the PC

    Sometimes it can happen that the connection of the Qiu to the PC via USB does not work properly immediately. The following tips:

  • My Qiu flashes red when I turn it on

    If the Qiu flashes red once, the device indicates that the batteries are getting weaker. Two red flashes indicate that the battery is about to be replaced. The Qiu flashes red three times when the batteries are exhausted. In this case, you should change the batteries as soon as possible so that there are no major deviations in the date and time function.

  • My Qiu flashes red when connecting to the PC

    If the Qiu flashes red once, the device indicates that the batteries are getting weaker. Two red flashes indicate that the battery is about to be replaced. The Qiu flashes red three times when the batteries are exhausted. In this case, you should change the batteries as soon as possible so that there are no major deviations in the date and time function.

  • My Qiu won't turn on anymore

    In this case you should change the batteries. Before changing the battery, unplug the USB cable from the USB socket if the Qiu is connected to the PC.

  • My Qiu only lights up green - no matter what I do

    Your Qiu is probably set to a level of difficulty (degree of rhythm) that is too low for you. In order for the Qiu to be able to offer dynamic HRV biofeedback, the device must be set correctly for the exerciser. The degree of rhythmisation should always be set in consultation with the treating therapist/coach. The degree of rhythmization can be set via the configuration

  • My Qiu only lights up red - no matter what I do

    Your Qiu is probably set to a level of difficulty (degree of rhythm) that is too high for you. In order for the Qiu to be able to offer dynamic HRV biofeedback, the device must be set correctly for the exerciser. The degree of rhythmisation should always be set in consultation with the treating therapist/coach. The degree of rhythmization can be set via the configuration

  • My Qiu keeps turning blue during the biofeedback exercise

    If the Qiu lights up blue, it is signaling that it is looking for a pulse signal.

  • My Qiu keeps turning blue despite using an ear clip

    There are two possible causes for this:

  • My Qiu constantly needs new batteries

    In this case, please make sure that the Qiu is not unnecessarily connected to the PC via USB. As long as there is a USB connection, power is consumed from the batteries.

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