hi sorry its been a while, the guide i used for the mtu is this one...... https://kb.netgear.com/19863/Ping-Test-to-determine-Optimal-MTU-Size-on-Router (i used www.bbc.co.uk instead of yahoo)
as for resetting the vr2800 theres 2 options, the auto setup which is done from the quick setup tab on the main menu, if you want to set it to access point (to work with another router aka the not so smarthub 2) then its advanced\operation mode then select wireless router mode, you will then need to go to advanced\network\lan settings and disable DHCP otherwise they will not play nice together.
As said previous im currently running a g.fast connection with a modem mtu of 1520 and the router is running 1492 (highest i can get it to go), im sure when running in vdsl mode it was set to 1482 or 3 and for me it worked fine, it is possible though my line is setup differently as i also had it connected via the annex a/l/m option and i had sra enabled (advanced\network\dsl settings) which according to the user guide is supposed to enable the modem to make adjustments on the fly in regards to line sync.
try following the guide first and see what you get
Updated router to latest firmware the beta one this morning.
Solid all day kids have not had problems using there home schooling apps.
But I've started having bad pkts
I would not worry about a few packet errors on the upstream path, as that part is mostly located at the highest part of the frequency spectrum, so I would not be surprised to see some errors.
done the ping test to get mtu settings and found that mine is exactly 1480 which it was set to automatically.
though that may be causing upload packet losses
Packet losses (CRC errors) are caused by uncorrected line errors, and nothing to do with MTU.
DLM (Dynamic Line Management) will try to reduce these by interleaving and Forward Error Correction, but this happens over a long period of time, so its important that you leave things connected up. As it takes many weeks for the line to stabilise,
all seems well its alot more solid than the bt smart hub. Albeit i still can't do a speed test on any device without it causing issues on all other devices.
But im getting alot better upload speed and download Speed is consistently 70mb