In several field setups we've noticed a strong interference from USB3 devices like hubs, cameras and Ethernet adapters to GNSS receivers.
When such interference occurs GNSS operation is affected and GNSS performance is significantly degraded. If you are using any USB3 device in your system please use caution and check for interference before your test. To do this keep all USB3 devices off and observe the CNo signal levels on the Swift Console Tracking tab; in open sky strong signals should reach about 55 dB-Hz level (with mini-survey antenna). Then start turning on your USB3 devices one-by-one and watch if their operation degrade signal levels. We've seen degradation up to 15 dB in some cases.
As a remedy we propose to use better shielded USB3 cables or remove such devices from your setup. Also USB2 devices we tried so far did not cause issues.