Our TIVO has recently started to take a long time between pressing buttons and it responding to the commands.
More frustrating is my OH will turn on TV to watch a planned recording ( i.e. F1) shows recording started at the correct time but isn't actually recording. it only starts to record when OH turns to that channel, might as well be back in the 80's
[MOD EDIT: Subject heading changed to assist community]
I sympathise with you - my box is not as fast as I would like (enough for me to never bother trying to use Catchup, for example - I use my smart TV's apps instead). This fault is a common occurrence on here, and this is a non-exhaustive list of things that have worked, for some people, some of the time.
In no particular order:
Sometimes, all the box needs is a full reset by powering down, removing the mains lead for a couple of minutes, and then rebooting it.
Sometimes the boxes are slow, because there is a fault on the line (low signal level, noisy line...) or the internal disk is faulty. This can be detected by calling 150, or by waiting for a few days for the mods to catch up here and check your Tivo out remotely.
Sometimes the boxes are slow because the disk has reached > 75% full (so try watching & deleting - but see next tip)
Sometimes although the disk may be below 75% full, there are a large number of deleted programmes in the Deleted folder (Go into this folder, and then delete all the "deleted" programmes a second time, but note that this means you will never be able to retrieve them)
Sometimes the disk is faulty, but that may be able to be cleared by you resetting the Tivo via the menu options - but note that this loses all your current recordings and planned recordings/series links
A suggestion I saw only yesterday from a forum mod is to go to the Home screen and on the remote control press Thumbs Down, Thumbs Up, Play, Play. If the code is accepted, you'll hear a 'ping' noise and the screen will go blank for a few seconds. (This apparently switches off some background processes - I have no idea what).
Sometimes the box is faulty and an engineer will have to be booked to swap the box out - again note that the engineer does NOT transfer your recordings or series links, so you will have to reload all planned recordings again
Sometimes, all the above is tried, and they are still slow. In this instance, if there are no other possible solutions for you, your options are live with it/keep complaining on the phone and try asking for service credits in compensation - especially if recordings are failing/cancel the contract/something else I haven't thought of.
Just another VM user trying to help, so no guarantees that my advice will work . If my suggestion is helpful, please mark it as helpful; it may help others. Just want to say "Thanks"? That's the Kudos button.