Background internet usage can usually be a reason a customer is experiencing slow throughput.
Check the MX480 for Wireless, Fibre, and DSL. Use EZlink NOMS to check realtime throughput for Cable Internet.
When a customer runs a speed test to see their internet bandwidth, remember the speed test does not take into account any background usage so it may show lower than expected. Background usage such as downloading large games/updates, icloud backup, any online backup, etc… can max out the upload and therefore make the internet seem like it is down. Assist the customer in determining which devices may be causing background usage that they are unaware of by shutting down one device at a time while monitoring realtime usage.
CPU limitations on lower end devices will limit the speeds a device shows on speed tests. For example, an i3 CPU may not be able to show speeds at 100Mbps download.
Check the hay.net website for Internet Packages if you think the customer may need to upgrade to a higher package.