Intermittent radio problems
But you're dead right about dodgy connections introducing interference, especially at lower frequencies.. There were tales year ago of a Port of London dredger suddenly playing BBC Light programme (BBC Radio 2 for all the under sixties😉) out of a rusty dredge bucket!😲
The taxi problem may not have been swamping as such, more interference from a sub-harmonic of the VHF frequencies they used.
Once did some interference tracing for the Home Office and NATS / CAA many years ago and poorly maintained VHF taxi radios were a regular culprit!
Cheers, Doug 😎