The IR light from an IQMX5 (depending on ambient light levels) may cause the visible light sensor to pick up so much IR light, that the camera goes in day-mode or black and white mode erroneously.
There may be an OID setting you can change to resolve this issue.
To easily change OIDs in IQmanager, please view the attached PDF document
The OID you are interested in is 1.2.32.11.8 and set the value to 'indoor'
As always, please verify that the camera has the most recent firmware available on the IQeye website.
For more configuration options, please see this tech tip:
Avoiding continuous day/night switching when using IR illumination
If the problem persists, please send the mac id along with troubleshooting details and screenshots to IQeye Support.