DL speed and ping big reduction overnight

[#1]

My download speed has been consistently 69 Mbps, and ping around 5-6 ms. Last night at around 5 am ping is gone up to 15 and speed is down to 57 Mbps.

I have reset the BT modem once. BTW test result: D/L speed 58.41, U/L 12.86, IP Profile 60.31
BTW result consistently used to be D/L 69, U/L 17.5, IP profile 73.2 Mbps
Could someone from Plusnet have a look at this please.

[#2]

So basically the FTTC DLM has added interleaving to your line because it has seen too many errors, the characteristics of this being ~4-5am resync, latency up and speed down.
There is nothing PN can do about it as the DLM is completely out of their hands, it would require an engineer visit to reset, at which point there is no guarantee that the DLM won't simply add interleaving back on after a few days.
If the DLM sees a low enough error count and general stability over the next 3-4 weeks then it may remove interleaving and you should see your speed/latency go back to where it was before this mornings resync.
Alex

[#3]

Quote

FTTC DLM has added interleaving to your line because it has seen too many errors...

Although those errors are invisible. My line was as stable as it could possibly be. Didn't have a single reset of BT modem or any indication of any errors whatsoever during the last 3 months. So DLM decided to interleave on a whim I suppose

[#4]

Have you unlocked the BT Modem? You'll be be to see them that way

[#5]

Hi there,
I can see you've raised a fault with us, we'll test your line to see if we can see what has caused this.

[#6]

Thanks Chris 

[#7]

Latency came down to its previous value of 5-6 ms at around 5 am, the same time it had gone up few days ago. I have just rebooted the BT modem and done the BTW speed test with diagnostics. IP profile has moved up from 60.08 Mbps to around 67 Mbps. The previous IP profile for the last 3 months had been 73.2 Mbps