Thought I better post the solution as it took me so long to reach this
stage.
The PCTel SiS7013 modem driver conflicts with both the OSSFree trident
driver and Alsa snd-trident driver use for the SiS7018 on-board sound.
You can either have one or the other but not both. This is a
documented but unsolved problem on the unofficial PCTel driver site.
See item 10...
http://linmodems.technion.ac.il/pcte...ctel-0.9.6/FAQ
I eventually found some posts on the Linmodems mailing list indicating
that a "Smart Link" driver would work. I downloaded the latest version
(2.8.3 at time of writing) of this driver but although I can now see
the modem with the sound enabled, it stalled when I dialed out.
Reading the archives I eventually found that only the 2.7 series would
work. Downloaded 2.7.14. Now it dials out but with what seems to be
glitches and gets the wrong number.
After further reading I found that there was a bug introduced after
2.7.10 that did this and that 2.7.10 was the last version that would
work with the pctel modem.
Now finally I can dial out and connect! This is on Mandrake 9.1 and
driver version 2.7.10.
The drivers are available here...
ftp://ftp.smlink.com/linux/unsupported/
Hope this helps some poor soul out there :-)
Fred.