Check out what Dale Frameli wrote on 29 Dec 96  01:13:00:
 >   I have an Amiga 3000/060, a pair of 28.8k/33.6k SupraFAXmodems and a
 > 115k multi-port serial card.  I'm having a problem (very frustrating)
 > with my ISP :(  I hope this is just a problem with my INIT string,
 > maybe you can tell me if that's what it sounds like to you...
 >   The main problem has been with getting connected and staying
 > connected...  Half the time I cannot complete the logon process, as my
Here is a part of the doc file from Miami I think this may be what your 
problem is:
Inactivity
----------
   Some Internet providers hang up the line if there is no activity on
the line for a while to prevent users from occupying lines that are not
really used.
   The "Inactivity" gadgets allow you to configure Miami to simulate
line activity even if you are not really using the line, so your
provider does not hang up.
   The gadget on the left sets the type of activity: PPP ping or ICMP
ping.  PPP ping consumes less bandwidth, but only works with PPP, not
with (C)SLIP, and does not have an effect with all providers. ICMP ping
takes up slightly more bandwidth, but works with both PPP and (C)SLIP,
and should have an effect with all providers.
   If you use (C)SLIP then choose ICMP ping. Otherwise first try PPP
ping, and if your provider still hangs up try ICMP ping.
   The gadget on the right sets the number of minutes between successive
pings. You need to experiment with that. Common values are 9 or 14, to
prevent hangups after 10 or 15 minutes.
   Note: You need to check with your Internet provider first if he
allows the use of this type of activity simulator. Some providers have
policies that do not allow it, and by using such a simulator you might
be violating their regulations. I will not be responsible or liable for
any consequences resulting from the improper use of this activity
simulator.
   Note: There are many reasons why a modem might hang up. One is an
inactivity timeout at your Internet provider, which should be prevented
by this function. However modems sometimes also hang up the line
because of line noise. There is no way to prevent this in software.
 >   Both of my 28.8k SupraFAXmodems (external), are flashed with
 > 1.440-25 and both use the same init string.  I have tried switching
How did you flash these. In the instructions from supra it says that AT**
puts the modem in flash mode. It doesn't seem to work for me.  Any help would 
be appreciated. 
As for your problem I would try Miami to see if helps.
Tom Pulles
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