The current NTE5a is brand spanking new. No need to replace - and it has a Mk3 interstitial filter.

In reply to a post by troublegum:

In reply to a post by Icaras:

Too bulky at the top too which means they don't fit in many recessed mounting plates which is just ridiculous.

They've made a spacer available (as a short term solution) for this very reason.

Yeah I know about the spacer. It shouldn't be required though.

In reply to a post by RobertoS:

They may fit one, just like old LJs were automatically replaced with NTE5s

The engineer was here yesterday. He didn't even suggest replacing the NTE5a for the NTE5c.

He just did a port shift and a D-side shift. Speed is still very slow compared to next door but the line appears to have more stability. His initial tests did show marginal AC balance on the original cabling. VOIP calls and SSH sessions which dropped regularly on the old connection look as if they might be stable now but it's going to be a few more days of use before this can be confirmed.