4.7.5 client crash when broker has 40-41 or more items in one category

Has anyone had this issue? I've looked at source codes from 3.9 where this issue does NOT happen and it's nearly the exact same code apart from 4.7.5 having split item selling packets being sent. Everything works fluently until a category has 40, 41, or 42 items in it. Any category with those numbers or higher will crash a client. I presume it's because a packet is too big but then I don't understand how a 3.9 client can handle all those packets just fine, which makes me think the 4.7.5 server is sending junk packets somewhere, but has anyone tried to combat this bug?

I've tried 4.7.5 aion-ger emu, 4.7.5 yayaya, and 4.7.5 gigatroon. They all had the same broker issue with a clean database installation and manually adding items to the broker. My 3.9 test was done with dwarfpicker's 1-click.