That is incorrect. Internet 150 should be more then enough to stream Youtube.
Try this.. in order.
Unplug ALL cable boxes (PVR and non PVRs)
Factory reset router (Red button on your 3200)
Wait in till Internet is back
If that doesn't work, you can try a process that will reset the STB or PVR back to factory settings (And shouldn't delete your recordings)
Unplug your box
Plug in back in intill you see Telus intill you see Telus
Unplug the box again
Do this 3-4 times intill you see Gears on the screen
It'll start "updating" - It'll have 2 different progress bars.
After it's done, try Youtube again.
If all that doesn't work, let me know