Only taxes the first item in cart...

Ever since upgrading to 1.3.8 I have what seems to be a unique problem... when someone adds an item to their cart, and they are from Maryland, it charges them state tax just like it should... just like I have it setup. BUT if they add ANOTHER item to their cart, the tax doesn't change. It only ever taxes the first item...

I've double checked all the tax setup info to be sure nothing was shifted after the upgrade but it all looks the same... I've gone through the check list... I've made sure they are all "taxable goods" items... I've deleted my MD setup for zones and rates and redid them... nothing seems to fix it!

In short, add a $10 item to cart and it charges 60 cents... then add another 1,2-200 items and the tax never changes.

Any thoughts?

Whoops.. forgot to mention the store...
http://www.easternperformance.com

From your Admin, uninstall and reinstall the tax module, does that fix it?

Sadly, no. Is it supposed to tax each thing and then add up, or just apply to the total? For this to happen I imagine it is doing it one at a time and then adding, but it never gets to the adding part...

If I was going to replace a bunch of files from a clean download to try and fix this issue, is there a particular group of files that would be a good place to start? I might just have some file that was corrupted somehow but for fear of losing mods I don't even remember doing anymore, I'd like to replace as little as possible...

A

The main calculating logic for taxes at the per-product level is done in /includes/classes/order.php ... where it presently calculates tax for each item individually.
But, if you've got numerous other addons installed, one of those could be adversely affecting things as well.
A list of all your addons would be useful information ...

Thank you for pointing me in the right direction... I actually didn't have too many add-ons at all with this store, but when I was having some issues with having a lot of options slowing down processing one of my programmers had edited query factory for me a bit to help processing. This helped the server drag quite a bit but it caused various issues here and there.. turns out this was one no one had noticed. When I replaced the whole "classes" directory with a clean one this was removed and all was well again. I guess I'll need him to tweak again for taxes!

Thank you!

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