Requesting a DLM reset

I’d like to request a DLM reset please, if possible.

My line is stable and error free (except for a few upstream errors) with the router current settings I’ve set, with 0 downstream CRCs errors for 8 days and no line disconnections (beyond myself resyncing the modem a couple of times, manually, as a test).

The downstream sync rate is fixed at approx. 39224 kbps at present. The router estimates that a ‘Max Rate’ for the downstream of approx. 55532 kbps is possible. The SNR margin remains at the default router setting and is reported to be 6dB.

I recently started using an Asus DSL-N16 Modem / router to connect to Cuckoo Broadband, which appears to be working just as well as the previously connected Cuckoo router.

How can I go about requesting a DLM reset, if the issue persists? Should I get the line / account holder to send an email to Cuckoo, to request this change?

Morning @cbdeakin,

We can request one, but only in specific circumstances. Your router will have had to held sync for a minimum of 3 days. If I go and request one without this, they will just tell me it needs to be raised as an issue because the system sees disconnections. It doesn’t differentiate between actual disconnections and you turning the router on and off.

If/when you’ve done this, get the account holder to email in and we can sort this.

Kind Regards

Good to know, I’ll leave it completely alone for a couple more days and see how it goes, thanks.

Hi, the request to reset the DLM has been sent :slightly_smiling_face:

Hi, many thanks for requesting a DLM reset from Openreach for my line.

Unfortunately, my line is still syncing lower than the ‘Max rate’ reported by the router (all settings at default). Maybe the router /modem is just calculating the max rate incorrectly (I suppose I’m sceptical as the distance to the FTTC cabinet in my street is likely 500-700 meters). Here are my line stats, 6 hours after the DLM reset was completed:

Just a few downstream CRCs so far.

As an experiment / test, before the DLM reset was done, I disabled the D3 VDSL2 band completely (higher frequency signal band), this cleared the downstream CRC errors over 11 days almost completely, but reduced the downstream sync to 39224 kbps, so not sure which is better really. I had almost no packet loss during Stadia game streaming sessions, so line errors appear to make a difference in some situations.

I’ll leave the connection alone /at default for another 48 hours, to see if anything changes, as I’ve heard it can take a couple of days to train the line.

@cbdeakin, I think we can get these errors sorted out for you, even at the higher speed. I’m not a fan of trading that much synchronisation rate for a reduction in errors.


It synced again, slightly higher at 51,707kbps, so I’ll see how it changes over the next few days, although the CRCs have increased a bit too.

EDIT - And again just now, interleaving has been removed now.

What’s an acceptable number of CRCs (Assuming these lead to ‘Errored Seconds’ ) to avoid the line being capped by the DLM?

There’s already 105 CRC downstream errors and 164 CRC Upstream errors, within 5 hours of the line syncing.

The line is otherwise stable.

Hello @cbdeakin theres no level of unacceptable or acceptable. It’s just whatever your line can handle. If they become too ferocious then the line will drop and resync accordingly.