There's always a very few incidental T3 timeouts in a DOCSIS hub's log, but they shouldn't be cropping up with the frequency yours shows (not to mention T4 errors, and Ranging Retries Exhausted which is a variant on a T3 timeout). So that log looks pretty grim, and the category and frequency of critical errors suggests noise on the upstream, which in turn is often associated with interrupted connections, high latency and poor downstream speeds.
It could be a noise fault with the gear in the local cabinet or upstream of that, in which case it will affect multiple customers, but should be fixed quickly without you needing a technician. Or it may be your cable connection is noisy or isn't properly setup, in which case you'll need a visit from a technician. Forum staff can advise when they pick this post up.
You might want to do a series of speed tests, or set up a Broadband Quality Monitor at Thinkbroadband, and see what that indicates, because even though your log is black and white proof of a connection problem that has been generated by VM's own equipment, the company is not always very good at reading and reacting to that evidence.
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