Unreliable Fax Detection

Are there any tips for getting fax detection working reliably?

Im using Trixbox, a TDM24xxp, and some POTS lines. Its probably also worth noting that these are BT lines in the UK.

Im not bothered about fax-to-email, forwarding to an extension or anything. All I need to do is ignore any faxes recieved on these lines.

Currently its pretty random sometimes theyre detected, sometimes theyre not. Success seems to vary from day to day. ie On friday, no matter what I tried, I couldn’t seem to get anything to detect at all.

what are you using for fax detection ? i’ve only played with on-hook fax-detection using NVFaxDetect and never got it to work reliably/at all.

for outgoing faxing i use the zapata fax detect option, and it seems fairly reliable using a TDM400.

Im using zaptel for fax detection. A 3 second wait seems to work most of the time, But sometimes 5 isn’t enough. It also seems that international faxes always get through.

I thought NVFaxDetect was only for detecting faxes over IAX or SIP trunks?

the synopsis for the application reckons all channels types, but i’ve only ever used Zap. then decided that fax2email for incoming was a lot less painful for my home setup, and hylafax more suited to anything serious.

So far, I haven’t managed to get NVFaxDetect to detect anything, I thought I’d read somewhere that it was intended for voip trunks.

I guess I’ll play round with it some more and report back.