Option vs Total Product Inventory

[scd1982]

I'm trying to figure out how to get the inventory for a product to update correctly when the product has several options.
For example: Product A has option 1, 2, and 3. Each option's quantity is 100 - Product A therefore has a quantity of 300.

When someone buys Product A with just one option, the correct decrease takes place, producing 299 total, 99 (option 1), 100 (2 option), 100 (3 option).

However, when someone buys two or more of Product A, regardless of the options, the inventory still only decreases by 1, producing 299 total, 99 (option 1), 99 (option 2), 100 (option 3). Is there any work around for this?

I'm using OC 1.4.9.4