I have a Topeak Panoram V16 wireless "computer" on the bike that gets most use. I didn't want a wireless set-up, but couldn't find a wired device which met my requirements in mid 2016. As expected it uses (single-use
cells/batteries) rapidly. It also suffers RFI problems, though until last week those only had a significant impact on cadence recording.
Last week I installed a shiny new B&M IQ-X front light on the fork crown, as a direct swap for the IQ Cyo (2014). When the light is switched on & I'm moving, the speed reads zero & the odometer stops recording distance. Further experimentation seems to suggest that while the supercap, that provides coulombs for the standlight, is recharging, the RFI is not as bad. That's still a very tentative conclusion.
I've read
100 Lux dynamo light. I don't think my problems should mixed up with that topic, since I'm fairly confident they're specific to the Topeak device.
Some rough geometric data may help any work-around thoughts. The distance sensor is below the IQ-X. The direct line between the sensor & the "computer" passes through the front brake caliper. The IQ-X has a shiny aluminium alloy (guess) case, which should work as a Faraday cage, apart from the hole in the rear for the on/off switch & its surrounding blue indicator. That is only about 5mm away from the (very notional) direct line from the sensor to some part of the "computer".
What suggestions does the forum have to either solve the problem or even suggest ideas that I might stretch into a solution with a bit of experimentation?