Hi, im brewing in kegmenters then putting straight jocky box with ice, to tap. Keg room temp, jockey box cools through line. I started brewing last autumn, and my first few brews were great. Im in SE QLD Australia. I usually use a coopers can (or similar), light dry malt and/or dextrose, some ginger/citrus pre-boiled to steralise and a bought refrigerated yeast. Moving into hotter weather, my brews have started giving people head aches the next day. I tried norway kveik yeast, aparently happy between 10-40 degrees celcius. Im not sure why the brews are suddenly giving terrible head ache hang overs. I thought perhaps fusal/methol alcohols from unhappy yeast, but changing yeast doesnt appear to help. Any ideas?