Sample Rate and H/W Buffer negotiation woes.
 

This post is primarily for PT 11 users on Windows using 3rd party USB interfaces.

I used to always run Pro Tools for Windows with Digidesign or M-Audio hardware, but recently changed to a 3rd party USB interface. Though it runs okay, I'm really disappointed by the lack of functionality of the ASIO USB driver that is supplied with the product. It seems to be just a generic core USB driver.

I can't change Sample Rate and I can't change H/W Buffer Size on the fly from inside Pro Tools as I used to. Pro Tools 11 needs to quit and especially Sample Rate changes can end up in a real mess.

My uneducated guess is that many 3rd party manufacturers are using the same OEM USB controller and relying on more or less the same generically written USB ASIO driver. It is not optimized for working with Pro Tools 11 for Windows. It is not optimized to correctly negotiate neither Sample Rate nor H/W Buffer Size with the Avid Audio Engine (AAE) on Windows.

Please answer the below questions to help me see what works and what doesn't. I'm equally interested in seeing what doesn't work as what does.

1. Can you change H/W Buffer Size from within PT without the need to quit PT?
2. Can you switch between sessions with varying odd sample rates from within PT without PT either locking up, refusing to play, or the need to quit PT? I am specifically talking about switching between 44K1<>96K, 44.1K<>48K and 48K<>88K sample rates.
3. Which audio interface did you use for these questions?
4. Which OS and version, PT version, etc.
   

Any comments are welcome. I know that Focusrite USB Windows users are hit by this. I'm amazed that so few people are complaining about it. Maybe they don't know how sweet it works with a proper driver?

Re: Sample Rate and H/W Buffer negotiation woes.
 

Thanks, very interesting read! I registered over at the tc forum just now, but can't find the beta forum you mentioned. Is the beta forum only available for registered beta members?

I still wonder why 3rd party developers like tc, Focusrite or Audient can't write a Windows driver for their hardware that will work 100% with Pro Tools - just like Avid can for Avid interfaces (and M-Audio in the past).

Perhaps Avid's drivers are not ASIO drivers. Perhaps they are interfacing directly with the Avid Audio Engine. Is that a possibility? And maybe Avid havn't provided documentation for 3rd party developers to write such a driver. I'm just guessing but it would explain the mess we're in.

Man, I wish Avid would enter and explain this once and for all.

Re: Sample Rate and H/W Buffer negotiation woes.
 

Hello!

1 Can you change H/W Buffer Size from within PT without the need to quit PT?
No

2 Can you switch between sessions with varying sample rates from within PT without PT either locking up, refusing to play, or the need to quit PT?
No

3 Which audio interface did you use for these questions?
Focusrite scarlett 18i20

Re: Sample Rate and H/W Buffer negotiation woes.
 

Thanks Sheldon! My situation:

1. Can you change H/W Buffer Size from within PT without the need to quit PT?
No.

2. Can you switch between sessions with varying sample rates from within PT without PT either locking up, refusing to play, or the need to quit PT?
No.

3. Which audio interface did you use for these questions?
Audient iD22 (USB).

Re: Sample Rate and H/W Buffer negotiation woes.
 

Here's another one of my interfaces:


1. Can you change H/W Buffer Size from within PT without the need to quit PT?
Yes.

2. Can you switch between sessions with varying sample rates from within PT without PT either locking up, refusing to play, or the need to quit PT?
Yes.

3. Which audio interface did you use for these questions?
M-Audio 1814 (Firewire).

Re: Sample Rate and H/W Buffer negotiation woes.
 

And another:

1. Can you change H/W Buffer Size from within PT without the need to quit PT?
Yes.

2. Can you switch between sessions with varying sample rates from within PT without PT either locking up, refusing to play, or the need to quit PT?
Yes.

3. Which audio interface did you use for these questions?
M-Audio Transit (USB).

Re: Sample Rate and H/W Buffer negotiation woes.
 

I thought this was a problem only for those using a focusrite interface.
Has anyone reported this to avid?

Re: Sample Rate and H/W Buffer negotiation woes.
 

I tend to focus on a product's strengths and work around the downsides. To make music. There will always be negatives - especially with a complex software product like a DAW, which have to run with a million pieces of hardware. I do enjoy working in Pro Tools and my Audient interface is sounding impeccable. Truly great sound.

What worries (or amazes) me the most is the initial reaction from the 3rd party developers when faced with these error reports on sample rate and buffer size issues (on Windows). It's like they never heard of the problem. Focusrite's initial reaction was clearly that. This problem has been there since the very beginning of Pro Tools supporting 3rd party hardware. That's several years now. Don't 3rd party developers test on Windows? Don't they have beta testers running Windows? Are they just accepting the issues? Is Avid to blame completely? Maybe 3rd party developers can indeed write a dedicated and 100% working driver for Pro Tools / Windows, but it's not worth the extra cost involved. One driver for all DAW's, take it or leave it.

I'm amazed that there is so little info about it. I'm also amazed that so few users are vocal about it.

Re: Sample Rate and H/W Buffer negotiation woes.
 

darbyshire, I'm sorry I got you all worked up :-). We're definitely on the same page though. This is a mess. A lot of it is due to focus, I think. Focus on Mac. Not Windows.

Re: Sample Rate and H/W Buffer negotiation woes.
 

What about RME interfaces like the Babyface? Surely someone has one and using Windows. With the reputation of RME, it's the one company I would think has this sorted.