Get online support
I have never run into this sort of issue with any other provider before. My download speed has suddenly become remarkably slower again. There is no reason this should be the case.
If I wasn't locked into a contract I'd change provider.
Would it be possible for someone from TPG tech support to run some remote tests or have a tech come have a look?
What troubleshooting have you tried so far?
For us to run remote testing, shoot me a PM with your TPG username or customer ID number.