Latency & Buffer Size: tone distortion issue with Tascam FireOne

Hi,

Live 8.3.4 on a MacBook Pro running OS X 10.8.2.  Tascam FireOne using CoreAudio drivers.

I'm attempting to set up the optimum buffer size using the built-in tutorial and I'm running into a curious problem.  Here's what happens:

1) Set FireOne as Audio Input and Output Device.

2) In/Out Sample Rate 44.1kHz.

3) Set Buffer Size to minimum (14), Tone Volume to -48 & CPU Usage Simulator to 80%.

4) Start the Tone.

At this point I get the expected crackly/white noise output.

5) Increase Buffer Size directly to 284 samples and hit Apply - Tone comes through perfectly, no crackle or pops.

6) Decrease Buffer Size slowly, hitting Apply after every change.

At this point, the Tone remains fine until I hit 45 samples, indicating that 61 samples is the optimum position.  

However, if I start at 14 and increase gradually to 284, hitting Apply after every step (14, 29, 45, 61 etc) then the Tone gets corrupted, and never resolves itself back into the pure 440Hz tone.  I'm no audio expert, so all I can say is that it sounds like a rough, undulating synth effect.  It'll change as the Buffer Size increases, seeming to get lower in tone.

Additionally, sometimes the same thing will happen if I set the Buffer Size directly to 61 Samples, and then turn on the Tone.

What makes this tricky is that I can't seem to determine a fixed way of reproducing this.  For example, in (5) above I said that moving it to 284 would cause the Tone to resolve, but in subsequent testing under identical conditions this didn't work, and I had to increase the Buffer Size to over 500.  It's all pretty strange.

Anyone able to offer any advice on this matter?

3 followers

Pinemartin 1 year ago | 1 comment

1 answer

  • Near Earth Object
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    0 votes

    Have you tried updating the driver, firmware, etc?

    1 year ago | 0 comments

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