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homesecurity · Today, 13:57

To clear up the confusion in the thread: you won't find downstream, upstream channels, or power levels in dBmV in your router settings. The other posters are describing standard Virgin Media DOCSIS (coaxial cable), but you are on Virgin's newer Nexfibre full-fibre network using the Hub 5x.

The Hub 5x is not a cable modem—it is an integrated XGS-PON Optical Network Terminal (ONT) and router combined. It runs over single-mode fibre using 1577nm downstream and 1270nm upstream optical wavelengths. The firmware is locked down by Virgin/Sagemcom and does not expose optical Rx/Tx power levels or low-level interface statistics to the user interface.

Regarding the periodic 30–60 minute packet loss spikes and BQM latency red blocks (especially seeing them at 2am when all your local devices are asleep):

1. **Shared Optical Splitter Dynamics (XGS-PON TDMA Contention)**
Full fibre on Nexfibre is a passive point-to-multipoint network (typically a 1:32 or 1:64 optical split in the street cabinet). While downstream data is broadcast to all ONTs, the upstream works on strict Time Division Multiple Access (TDMA) managed by the Optical Line Terminal (OLT) in the local exchange. If another customer on your optical splitter has a failing optical transceiver, bent dropwire, or dirty connector that leaks continuous light ("babbling ONT"), it pollutes the upstream timeslots. When the OLT loses synchronization, all users on that optical splitter experience periodic bursts of packet loss and latency spikes until the OLT isolates the offending serial number.

2. **Hub 5x ICMP Deprioritisation vs Real Traffic**
The Hub 5x processor aggressively deprioritises WAN ICMP echo requests (which is what the thinkbroadband BQM tool sends). During routine TR-069 management polling, DHCP lease refreshes, or DNS cache syncs, the Hub 5x will drop ping packets even while real TCP/UDP payload data continues passing without issue. Next time your BQM shows red packet loss, run an MTR or continuous ping to both your default gateway (192.168.0.1) and an external target (e.g. 1.1.1.1) to see if local latency spikes match WAN drops.

3. **10Gbps LAN Port Auto-Negotiation Bug**
If you have any wired device or switch plugged into the 10Gbps port on the back of the Hub 5x, check your network adapter settings in Windows. Earlier Hub 5x firmware revisions had an issue where Energy Efficient Ethernet (EEE / 802.3az) and 10G-to-1G auto-negotiation caused periodic buffer stalls and micro-drops. Try disabling "Energy Efficient Ethernet" and "Green Ethernet" in your PC's NIC properties, or plug into one of the standard 1Gbps LAN ports instead.

4. **What to ask Virgin Media for next**
Fibre cleaning at your wall box only rules out dirt on your immediate SC/APC splice. If the spikes continue, contact Virgin and specifically ask for the case to be escalated to their Fibre Operations / Networks team to check the **OLT port optical stats** for uncorrectable Forward Error Correction (FEC) errors, upstream optical power drift, and rogue ONT alarms on your passive PON segment.

Today, 13:57	#12
homesecurity Mr Gary Pearce Join Date: Nov 2026 Location: United Kingdom Services: TV INternet CCTV Home security Alarms Hikvision Dahua Ajax Posts: 2	Re: Ping spikes, lags and packet losses To clear up the confusion in the thread: you won't find downstream, upstream channels, or power levels in dBmV in your router settings. The other posters are describing standard Virgin Media DOCSIS (coaxial cable), but you are on Virgin's newer Nexfibre full-fibre network using the Hub 5x. The Hub 5x is not a cable modem—it is an integrated XGS-PON Optical Network Terminal (ONT) and router combined. It runs over single-mode fibre using 1577nm downstream and 1270nm upstream optical wavelengths. The firmware is locked down by Virgin/Sagemcom and does not expose optical Rx/Tx power levels or low-level interface statistics to the user interface. Regarding the periodic 30–60 minute packet loss spikes and BQM latency red blocks (especially seeing them at 2am when all your local devices are asleep): 1. Shared Optical Splitter Dynamics (XGS-PON TDMA Contention) Full fibre on Nexfibre is a passive point-to-multipoint network (typically a 1:32 or 1:64 optical split in the street cabinet). While downstream data is broadcast to all ONTs, the upstream works on strict Time Division Multiple Access (TDMA) managed by the Optical Line Terminal (OLT) in the local exchange. If another customer on your optical splitter has a failing optical transceiver, bent dropwire, or dirty connector that leaks continuous light ("babbling ONT"), it pollutes the upstream timeslots. When the OLT loses synchronization, all users on that optical splitter experience periodic bursts of packet loss and latency spikes until the OLT isolates the offending serial number. 2. Hub 5x ICMP Deprioritisation vs Real Traffic The Hub 5x processor aggressively deprioritises WAN ICMP echo requests (which is what the thinkbroadband BQM tool sends). During routine TR-069 management polling, DHCP lease refreshes, or DNS cache syncs, the Hub 5x will drop ping packets even while real TCP/UDP payload data continues passing without issue. Next time your BQM shows red packet loss, run an MTR or continuous ping to both your default gateway (192.168.0.1) and an external target (e.g. 1.1.1.1) to see if local latency spikes match WAN drops. 3. 10Gbps LAN Port Auto-Negotiation Bug If you have any wired device or switch plugged into the 10Gbps port on the back of the Hub 5x, check your network adapter settings in Windows. Earlier Hub 5x firmware revisions had an issue where Energy Efficient Ethernet (EEE / 802.3az) and 10G-to-1G auto-negotiation caused periodic buffer stalls and micro-drops. Try disabling "Energy Efficient Ethernet" and "Green Ethernet" in your PC's NIC properties, or plug into one of the standard 1Gbps LAN ports instead. 4. What to ask Virgin Media for next Fibre cleaning at your wall box only rules out dirt on your immediate SC/APC splice. If the spikes continue, contact Virgin and specifically ask for the case to be escalated to their Fibre Operations / Networks team to check the OLT port optical stats for uncorrectable Forward Error Correction (FEC) errors, upstream optical power drift, and rogue ONT alarms on your passive PON segment.