Theo,
You should look at the style guides for programming. Your diagram covers about three times as much space as is needed and is hard to read. Diagrams (and front panels should not be larger than one screen. Wiring should go left to right.
You also need to learn more about dataflow. Your Write to Text File appears to be a header for the columns in the file, but it conceivably could be written after the data! A simple rewiring of the refnum in and out can take care of this.
The conversion of the path to and array of strings and back seems to have not purpose.
On to your primary question: You are reading 1 sample on each of the (three?) channels each time the loop iterates. If the Record to Disk is true, you also write once per iteration. Disk writing can take time and the amount of time can vary from call to call depending on what the OS is doing. So, to speed things up, do two things. One, read multiple samples at a time. And, two, accumulate data until you have a bunch and then write to disk, outside the loop. The best way of doing this depends upon the amount of data and other things.
Lynn
