Umm, now that you mention irqtune, that rings a bell. I will try it.
I received a suggestion turning off VJ compression, no change.
>
> It is likely that supposedly identical models of those modems with slightly
>different firmware revisions
> would not show the same problems. I know of at least 150 different firmwares on a
>single model of
> "sportster" modems with nothing to tell them apart for the consumer.
>
> What you probably want is irqtune to move the serial ports up in the priority stack
>for interrupt
> handling. If you search the archives with the keywords "Civileme" and "www.best"
>you will likely find
> the URL explaining the principle and providing the download.
>
> Civileme
