Correct Jib fairlead position will help
If the jib leech is vibrating while on a beat, then move the fair-lead car a bit forward until it stops.
If the jib leech is vibrating while on a reach, then move the fair-lead car WAAAAY forward until it stops. Most cruising folks NEVER move their move their jib fairlead cars forward when changing to a close or beam or broad reach ... and that causes the cledw to 'rise', the topmost leech area of the sail starts to 'flog', etc.
When the 'genoa clew goes forward' so does the fairlead car !!!!!!!
If all the above doesnt stop the flopping/vibrating you can also 'release some jib halyard tension' which will cause the leech to 'stand -up' and get tighter. Dont over-do the halyard 'easing'.
Axiom: whenever adjusting anything that puts or changes the tension on one 'side' of a triangular sail, there is ALWAYS a 'second adjustment' needed to correct the distortions of sail shape cause by the first.
In the above examples, if the jib sheet 'goes forward', the clew also goes forward and UP. To counteract the 'up' you need to pull it back down again by moving the jib car forward.
BTW - I envy your trip .... their is no better food/cuisine in the entire western hemisphere than on the "fleuve Saint-Laurent" or the Gaspé.
;-)