Quality of knock-off brands like Jinhao and Wing Sung is going to be pretty universally shit. You can usually buy a handful and one will be at least decent though.
One thing you could check - any moisture present in the cap can tend to draw more moisture out of the pen. You could dry rinsing and then thoroughly drying (Q-tip, compressed air, whatever) the inside of the cap, dab the section and nib to make sure it's fully clean, let it dry for a bit (you can shield the nib from air with a cloth to keep it from fully drying out) and then try writing with it and capping it again to see if it sorts itself. If not it might just be way too wet and dumping ink in the cap, or you're knocking the pen around too much causing ink to leak from the feed. This is all of course assuming it's otherwise properly tuned.