Slight noise and high SNR

[#1]

Hi,
So I recently switched to fibre and I've had a slight noise on the line ever since, it's a faint hum but can hear it with 2 different phones. I'm on quite a long line 1.5km from cabinet so never expected great speeds but thinking with the noise it may not be getting the max I could get. The SNR usually is around 7+db and will try for 6db then jump back to 7+. I reported it before but was worried that I would be charged if no fault was found so cancelled the visit as I'm currently using an unlocked HG612 modem (to monitor) and my own Huawei ws5200 router. The plusnet and BT routers have all had issues on my line (BT would reboot and plusnet would report incorrect password after a few days if it didn't drop also) so invested in my own kit. It's currently been very stable and up for 12+ days without incident but I was hoping I could get SNR to 3db similar to what I had on ADSL and get from my current 19mb to the checker reported max of 24-26mb. Plusnet checks report no fault found. I have no extension sockets connected and the noise exists on the test socket.
Would I be punished/charged for using my own kit if the engineer visits to report to fault found.
Thanks

[#2]

I'd say you're over thinking this one. Targeting a 3db snr target is maybe optimistic on a long line but either way you've already identified a noisy line.

As for charging, if the fault was due to your own router then you'd be charged. That said if two other routers have a had issues it's unlikely to be your own kit. Easy enough to rule out anyway. Remove the broadband side entirely, plug in just a phone into the test socket and run the quiet line test , 17070 option 2 and see if the hum remains.

If it's still noisy and you've already ruled out handset issues by virtue of trying 2 phones then you have a phone line fault which will need reporting and likely an engineer. Ignore the broadband behaviour for now until this hum is addressed as it's likely the cause of your reduced performance anyway.

[#3]

I've tried a phone into the test socket and yes I still get the humming noise. This is without a filter connected as I have a prefiltered master socket.

I'll get it logged and see how I get on.

Thanks for your advice!