You are checking over an Ethernet cabled device aren't you? I ask because VM don't guarantee speeds over wireless, and you've not specified.
Are those speeds consistent, or do they vary?
1: Let's get all your modem stats.. Goto to http://192.168.0.1 (or http://192.168.100.1 - if in modem mode) but don't log in. Click on "router status", and copy & paste the data from each of the tabs.
2: If you haven't already, please setup a Broadband Quality Monitor and post a link to your live graph. It monitors your connection 24/7 and provides excellent diagnosis of any underlying issues.
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