Internal Storage VI error

[jreif]

I am acquiring multiple channels at 5KHz (continuous) and down-sampling some of them to then store using the storage VIs. There is also some online signal processing (i.e. FFT) and visualization. On the block diagram I open a file using the event structure on a button press and then my acquisition loop includes the Write Data subVI. But it seems the overall speed of the VI slows down considerably when recording starts and even seems to fall behind acquisition speed (graphs show changes in waveform later than when they actualy happened). I then get an error that shows up periodicaly at the storage VI that says "Error -2500: Internal storage VI error" and thats all the info I get. When that error happens I think I also loose some data evident from warnings I get on my filters that notify me the data has lost continuity. Something is wrong but I can't figure out what. HELP anyone? Thanks.

[Brett_B.]

How are you writing the data to a file? Are you streaming the data to a binary file?...byte at a time or are you writing array blocks? Are you opening and closing a file in a loop?...because that would cause serious speed issues with your program.

-Brett

[jreif]

No, I am not opening and closing inside the loop. I open the file outside the loop via en event using "Open Data Storage" VI, and then I am using the "Write Data" VI (TDM format, writes 2 files, one XML and one binary if I understand correctly the format). The Write Data is used inside an acquisition loop that collects 7 (or 9) channels at 5KHz (500 samples per loop, so 0.1sec of data per loop) but then resamples two of these channels down to 400Hz and 50Hz respectively, the rest stay at 5KHz. So yes, I am streaming the data and I assume it writes it in blocks on each loop (not byte at a time).
Does this help clarify?