Shipping Tax not Carrying Through to Order Details

Hi Team,

I have standard tax of 10% applied to both products and shipping.
1. In the customer CART and CHECKOUT screens included tax calculations are incorrect. (the actual total order value always remains correct)
2. When placing the order TAX totals change again to remove the included shipping tax. (the actual total order value always remains correct)

eg:
Product – $55
FlatRate Shipping – $11
Total – $66.00 (includes $7.00 Tax) —> this should be $6.00 tax. If I change the shipping to free local pickup, this changes to the correct $5.00 for only the product tax.

After customer clicks on ‘Place Order’, the included tax total reverts to only the product tax.

eg:
Product – $55
Shipping – $11
Total – $66.00 (includes $5.00 Tax)

I can replicate the issue using the australia post module:
eg:
Product – $55
Austpost Shipping – $10.20
Total – $65.20 (includes $6.02 Tax) —> this should be $5.93 tax. If I change the shipping to free local pickup, this changes to the correct $5.00 for only the product tax.

After I click on order, the order details only include the product tax.

So I have 2 issues.
1. CART & CHECKOUT Pages: Included shipping tax is incorrect
2. On placing the order, included shipping tax is removed.

WC Version: 2.4.7
WP Version 4.3.1

My System Settings:

General:
Base Location: Australia
Sell to Specific Countries Only: Australia

Tax:
Enable Tax Calculations
Prices Entered With Tax: Yes, inclusive
Calculate Tax Based on: Shop base address
Shipping Tax Class: Standard
Display Prices During Cart & Checkout: Including Tax
Display Tax Totals: as a single Total
Standard Class Rates: Including Shipping

Shipping Method Used: AustraliaPost Shipping Module

Please help!

https://wordpress.org/plugins/woocommerce/