There's usually a clause on every subscription terms and conditions that the terms themselves are subject to change. So even though your subscription papers do not have the clause thats because you're having the older revision. And your form has this clause to carry forward to the new one. Yes, in this case you have signed the old one so the new one shouldn't apply. Not so easy unfortunately. This is because when you sign it there's another clause saying you agree with the clause already mentioned.

This isn't a Service Level Agreement (SLA) so the service provider reserve the right to change their terms of service. As consumers the status quo lies on the service provider. We can only vote with our pocketbooks.

Anyway, that term is stupid and they are shooting at their own foot. As an ISP your core service is to provide means of connection to the web (www). And the internet is largely based in out of country (sorry, Malaysia didn't pioneer the internet, nor we are the greatest economic power in the world). So if you cannot guarantee that very fundamental core service, then what right do they have to be an ISP? Probably it only applies to consumers like us. So I guess they are bullying us and do not value us as their customers. Maybe we're not their profitable customers. The large corporations or SMEs are.

Agree, my temporary solution is to use a Singapore proxy.

Broadband QoS in CMA 1998 still applied to every ISP.
If you are getting less than 80% of your speed for 95% of the time (by doing speed test on TM website) then you can launch a complain to SKMM.
QoS