I take it you are connecting over wifi? But are the issues only evident on wifi connections or do you see them at the same times on devices connected on ethernet cables? If you don't know, can you check to help diagnose whether it is just a wifi issue or it could be network connection/Hub related?
If it is just a wifi issue - see this.
To address the wifi issues, VM now supply “wifi Pods” (no longer doing cheap and cheerless “boosters”). However, their Pods are only free to customers on the 1GB, Volt (or old Ultimate Oomph) packages - is that you? If so they are worth trying - they should work for you. VM Wifi is now “guaranteed” to 20 Mbps/room and it’s now called… Wifi Max see…….https://www.virginmedia.com/wifi-max
You can call 0800 064 3850 to order the first one - or follow instructions on that website - or just wait here for a VM person to respond in a day or two and they will sort the first one for you . If you call dont get fobbed off by the offshore CS agents' saying you aren’t eligible it will be £5 or £8 month - you are… and it wont be - just look on the webpage.
If not free to you… you will be charged £8/month (note - BT charge £10/mo for their whole home wifi solution). It’s a simple solution and should work for you. However, you would soon pay off that cost by buying your own wireless solution that will be yours to own and use forever, although the VM Pods should be a simpler option.
If you do want to invest in better equipment, you would need to get either a… (1) Mesh System, (2) Wireless router, (3) Wireless access point (4) A combination of (2,3).
£30-100 (that’s ~4->12 months of Max Pod rental) should sort it for most customers with an average property and usage.
I do not work for VM. My services: HD TV on VIP (+ Sky Sports & Movies & BT sport), x3 V6 boxes (1 wired, 1 WiFi, 1 on PA) Hub5 in modem mode with Apple Airport Extreme Router +2 Airport Express's. On 250Mbps, Talk Anytime Phone, x2 Mobile SIM only iPhones.