It seems that the ws.trades method delegates to the aggTrades endpoint:
https://github.com/HyperCubeProject/binance-api-node/blob/master/src/websocket.js#L165-L167
instead of using the trades endpoint as indicated in the readme:
https://github.com/HyperCubeProject/binance-api-node#trades-1
Is this a bug?
UPDATE: fixed the last link to point to WS rather than REST