I've never had this problem, so it's very interesting to see it pop up again.
Knowing you've tried the above suggestions in this thread, and that your alt is picking up these items without a problem...
Have you used all available bots out there? (Carbon, LeBot, Armjldian being the most common) and results been the same?
I know you've tried (up/down)grading your bots, and your Flash Player (curious, what version do you use?), and you can pick these items up manually?
Have you tried custom bots that only pick up one, the other, or both items and seen if they disconnect?
Another thing is that some pre-made bots in the clients pick up all drops at the same time, perhaps a custom one that does them 1 by 1 will avoid disconnections?