Comrex ACCESS MultiRack Product Manual page 85

• At minimum, connect a few minutes before airtime to assess the connection quality. Setting a MaxRate
on the POTS codec is highly recommended. MaxRate usually should be set at a level or two below the
maximum unrestricted rate. This will provide a "guard band" against noise and distortion which may cause
errors on the line.
• If operation starts to degrade after a long period of connection, it's possible the phone line parameters
have changed. These parameters are affected by factors such as time of day, weather, and geographic
location. The modems should be given the opportunity to renegotiate for these new parameters.
• When experiencing low connection rates or errors, try re-dialing. If that does not help, dial from the other
end. If the call is long distance, forcing the call to another carrier may resolve the issue.
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