I do not think it is the wifi specifically, but is related to some radio interference generated by the train. WiFi as a whole is not a 'clean' transport and results in a large number of re-transmissions which are normally handled by a buffer in your equipment so you do not notice an issue. However, as the number of re-transmissions increase the buffer is overloaded and drops data. It is most noticible on realtime and near-realtime transmissions such as audio and video streams.

Changing channels will not help if you are experencing interference with the feed to the house, so I would start with the cable provider and then FCC to see if they can help isolate the issue.