Crosstalk on blocking channels
Crosstalk has been found to be an issue when connecting the cable shields of two (normally) isolated blocking channels together.
When the two channels are isolated, no crosstalk is observed on the other channels. However, when the two channels are connected to a receiver that connects the cable shields to a common return path (ground net), crosstalk in the range of 4 Vpp is noticed. This crosstalk can be seen in the scope capture below: