SagemCom F@st 3864V3 Wifi Issue



I am facing a lot of Wifi issue with my optus F@st 3864V3 router. Randomly a connected device stop working. After disconnecting and re-connecting it become fine. So far i have not seen any problem with LAN. As some people suspected that it may be due to dual WIFI so i shutdown 5Ghz but problem still persist. Does any one has any tweak to fix it up. It seem optus prefers use of cheap modems at the cost of losing customer. If this does not get fixed there is no chance i will continue with Optus.


PS: I have already done basic troubleshooting. The issue is not with WAN connectivity. Restarting/reseting etc has been done multiple time. 

Re: SagemCom F@st 3864V3 Wifi Issue


It seems to be the topic of the week and I have seen no answers to the WiFi issues with that device. I think a post yesterday had the opposite issue with 5Ghz working and 2.4Ghz randomly disconnecting. I think short of doing a reset and possibly changing the WiFi channel there are no other options. From all reports tech support thinks that restarting your modem a couple of times a day is normal operating procedure. I think I would be having another word with support and let them know of your desire to go elsewhere if the problems can't be resolved.

Re: SagemCom F@st 3864V3 Wifi Issue


I am not sure wheyher the issue is with 5Ghz i just shutdoen 5Ghz to see if thats the root cause. Also I donnot think that it is normal to restart router 2-3 times a days. 

Re: SagemCom F@st 3864V3 Wifi Issue


No it's not normal to restart your modem several times a day. I would speak with support again and tell them this is not a solution to your problem.

Re: SagemCom F@st 3864V3 Wifi Issue


Its normal to restart your router several times a day - !!  they are low quality.  When will Optus realise that inferiour products will come back to bite them with replacment costs and time and effort spent is support etc.  We are on our 3rd SageCom - (SIGH)  time to get something that works!


Note: each time there is an NBN outtage (OFTEN) we find that everything needs rebooting - and you have to do it in the right order - start with the modem - then the router - then each divice.  The Sagecoms are particaltry bad at distributing IP addresses - I think this is their major failing - they freeze and dont issue any new IP addresses so someone will have connection but no one new can connect.  = Time to reboot. 

Re: SagemCom F@st 3864V3 Wifi Issue




switched from optus hfc to optus nbn hfc so they gave me the new sagecom black modem.


All mobile devices perform bad with cutoffs and very choppy downloads. This includes samsung phones , apple tablets, dell laptop


download can go from 40mbps to 5 to 18 in seconds


ookla speed tests are also very strange with very low mbps and then moving up slowly to 40mbps


The hard wired pc has no such issues


The old optus modem was a dream, never had issues so i know its not my devices


I also turned off 5ghz and made sure to pick a 2.4ghz channel with no interference. 


All speed tests were done within 4m of modem and with no obstructions


i could get another wifi router but that means i have gone from one modem to 3 modems (nbn cm8200, optus sagecom , 3rd party wifi) which is ridiculous, soon ill need a rack to hold all the equipment.


Optus u need to fix this or im gone



Re: SagemCom F@st 3864V3 Wifi Issue


Hi Mel20000,


I have been through 3 x SagemCom routers - I changed from cable to NBN 4 months ago - frankly the Sagecoms are bad !  They freeze regulalry and cannot handle sub-networks with another router even though they are meant to.  I have ditched Sagecom ( spending hour /days in that bloody phone cue with OPtus support - WILL SOMEOME CHANGE THAT *&^%$ MUSIC!!! Smiley Happy )and have gone back to our Apple Airport extreme - what do you know - absolutely rock solid on NBN - excellent AC wifi no probs with 2.4/5ghz etc.  just set and forget. We have it loaded up with hard wired network and at times 8+ wifi users.  Our unit is 6 years old and Apple are going to discontine them ( if they havent already Smiley Sad ) .  


The Sagecoms are dodgy on both cable and NBN.  Optus have gone for CHEAP Vs something that works - I cant beleive the grief this is causing them - I really feel for the support staff - The exec that made the decision to go SAGECOM should be .........


rebooting the modem on a daily basis is now a thing of the past. Pfew! Cant remember when the Airport was last booted? 

Re: SagemCom F@st 3864V3 Wifi Issue


It's one of the most common complaints we see on the forum and it's something that we've continually brought to the attention of product/networks. 

In April, we did receive comm's from our Network team who'd advised that a lot of the WiFi instability issues we've been seeing have been resolved by the release of firmware update 10.7,1. 

The most current version of our Sagemcom modem is the F@ST3864V3HP.

I don't know whether it's a matter of luck on my side, but I'm using the V2 and I rarely experience drop outs. Granted, there's only a couple of users in my home, but we still have a number of our devices connected to WiFi at the same time. 

Re: SagemCom F@st 3864V3 Wifi Issue

[ Edited ]

FWIW, I have used the AC V2 and, now, AC V3 variants on FTTN since October 2016 with absolutely no issues other than one which was my fault; I had a USB wireless adapter which could not connect to 5GHz channels 149 and above.


I live in NSW Central Tablelands and the WiFi environment is very friendly - hardly any strong signals near me. Mine is not a large house but everything is connected to the router by WiFi. So, I suspect that there may be two issues with the router: WiFi environment, and incompatibility with some attached wireless devices.


I consider that a good move would be to allow a better choice with the 5GHz channels selection - currently automatic or 36/80. Why not allow any 5GHz channel to be selected? Furthermore, it would be nice if selection of 2.4 GHz channels 10-13 is added (rather than stopping at 9).


(edit) Forgot to add my Software version is 10.87_F@ST3864V3AC_Optus.

Re: SagemCom F@st 3864V3 Wifi Issue


Yeah, Im in the city, yes we have a large house, yes the kids friends want to come around and the first thing that want to do is jump on the wi-fi - we have mac and android demand.  Im not moving to the bush or seeing the need to get an IT degree just to run my modem - it works or it doesnt!

Sagecom doesnt work - 12 months of greif trying to make it work and as previsouly mentioned spending far too long on the OPtus help line, finally talking to embaressed help staff that that start with "have you turned it off and on again".  

I have 3 Sagecoms that are about to go to e-waste as it seems Optus is disinterested in taking them back.


I have a router (Airport ) that does work!! end of story - last comment - I want to get on with my life!

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