Troubleshooting Mobile Broadband for Slow speeds

This article will guide you through the troubleshooting for speed issues on a Mobile Broadband service.

Note: As of 13 October 2015, Mobile Broadband hardware and services are no longer sold by the iiNet Group, however existing customers may continue their service and request a replacement SIM card if necessary. Existing Mobile Broadband customers can view and swap plans in Toolbox (My Products > Broadband > Change plan) or by calling us on 13 22 58.

Select one of the links below to jump to a query:

  • Speed test results much slower than usual
  • You experience slow speeds for all internet functions, not just a specific website or program
  • Some websites don’t load properly or suffer lag
Potential cause
Try this:
Data congestion If you’re using a WiFi Hotspot, reduce the number of devices connected at the same time to rule out data congestion.
Weak WiFi signal If you’re using a WiFi Hotspot, follow this advice to obtain the best WiFi signal strength possible.
Mobile network congestion iiNet Mobile operates on the Optus network. If you only experience speed issues during peak hours (e.g. 5PM-8PM) or during crowded events such as music festivals, then the cause may be network congestion.


  1. Check the network coverage for your area.
  2. If your location only has coverage on the 3G network instead of the 4G network, please be aware that 3G has a lower speed potential than 4G. Similarly, a 4G mobile broadband service will use the slower 3G network by default if you are outside of a 4G coverage area.
  3. Run an antivirus/anti-malware scan using the antivirus software on the computer or device you’re using. Please contact your security software’s Customer Support if you need a hand with this.
  4. Test your speed while firewalls/antivirus software is temporarily disabled. Please contact your security software’s Customer Support if you need a hand with this.
  5. If you still have speed issues, please call our Support Team on 13 22 58 for further assistance.