Help with troubleshooting

Hey all,

Looking for a. little bit of support or some tips when it comes to troubleshooting. I feel I have tried most of the usual stuff and can't seem to find any threads that are similar to what I am experiencing.

Device: Firestick 4K with Ethernet adaptor.
ISP: TalkTalk 75mbs
VPN: SurfShark
App: TiviMate Premium

The issue I am having is with my iPTV. Every 5 - 10 mins I get a buffer for maybe 3-4 seconds then it starts again but it throws the audio out. Changing channel and going back seems to resolve this audio issue until it buffers again. Just to be clear I am talking about the buffering as the issue not the audio sync.
Say for example its happening on MTV FHD

Ive spoke to someone who "apparently" has the same provider as me and has tried the same channels, they are having 0 issues which would put the ball in my court.

I have made sure that none of my other devices are using the connection as I only have 1 on this provider as trialing a month.

What I've tried:
- Changing Buffer size on TiviMate
- Changing VPN Server & Protocol
- Clearing Cache
- Resetting router & Firestick
- Changing to HLS

If anyone has any other recommendations would be appreciated, maybe a specific VPN location they prefer. Im based in the UK.

Thanks