I need the shop to apply 19% VAT on all products.

But when I enter a nett price for a product the shop automatically fills in the same price as gross price, and vice versa.

Here's my settings:

Display Prices with Tax - true
Display Prices with Tax in Admin - true
Basis of Product Tax - Shipping
Basis of Shipping Tax - Shipping
Sales Tax Display Status - 1

I have 1 tax zone called 'all'
1 tax class called 19%
1 tax rate of 19%

Tax Decimal Places: 2

Any idea what else to check?

Thanks,
Ralf