das16: Spurious interrupt and Sampling frequency

Hi,

I am working around the cmd.c-demo with a cio-das16/330 board. The board is installed in the 'compatible mode' which according to the board's manual would allow a sampling frequency of 150 kHz through DMA. When setting 'freq' in cmd.c to 62500 (that's 16000 ns), sometimes I get "residue > transfer rate!" which seems to me as I am close to the sampling capacity and sometimes not. The message appears when closing the program, thus after having read the buffer.
Is this as expected? Maybe --fmhess-- knows?

When the sampling frequency is below this limit, I get the message "comedi0: das16: spurious interrupt" when stopping the progam (CTRL-C) as it halts (as usual) or trying to stop it more softly with first a comedi_close(dev) and then an exit(0) in the code.

I had previously a PnP internal modem installed, which the isapnp-tool assigned IRQ5, the same as I have to use for the board. So, I took away the modem, and consequently no isapnp is visible in the /proc library since I have no other ISA-PnP-cards installed. There is no other device using the IRQ nor the DMA. Does anyone know if I should ignore this message or do something and if so; what? Does it matter to recompile the kernel and comedi when the hardware set-up of the computer has changed?

Grateful for any clues or comments...

/Daniel L Sandin