What settings are you using in your session? The clock on the HD24XR has to be set to the correct sample rate as well as set to Optical clock source. The Presonus has to be at the same sample rate and set as master. The DAW program also has to have the session set to the target sample rate. An important thing to check is to make sure you are not feeding the HD24 looped audio as this will cause a nasty squeel.

Sounds like a clocking issue, as Jack said...
I used the Firestudio for awhile and sometimes ran two Digimax LTs into via lightpipe.
Sometimes, one wouldn't play nice syncing to the FS... and that was exactly the sound I got.

Not sure if it's allowed for in this setup, but it might be worth making the HD24 the master, and slaving the FS to it.
Typically you want your interface to be the master, but if it ain't clocking right, try it the other way.

Or try an ART Syncgen.

Now wait just a minute here... Are you talking about recording onto your HD 24xr from your Presonus Fire studio via light pipe to the HD 24xr?

Or are you trying to feed your HD 24xr recordings into your computer? If you are trying to do that, you don't need the Fire Studio. You need the hard drive adapter to FireWire not the Fire Studio in real time. You don't even need that, you just need the HD 24 tools software you already read about at the Yahoo site. There is absolutely no reason to be trying to clock this thing into the computer as you don't need to do it this way. This is not the way to do it.

Clocking for recording purposes & clocking for playback purposes have to match and the HD 24xr's clock is not accurate at 44.1 kHz. So you are going about this entire thing in the wrong way. The analogy here would be that you'd like to drink and drive and don't understand why that tree got in your way. So, you really will cause yourself more grief trying to get your tracks into your computer this way than just using HD 24 tools on the HD 24 hard drive utilizing USB 2.0 or FireWire, it won't matter and no clocking will be necessary. Same way to transfer back to the disk drive & play out through the HD 24 after you have processed your tracks and want to go out from your HD 24 through your 24 input vintage Neve for mixing in analog, otherwise, that ain't what you're doing. So the only thing that needs to be clocked is your microphone preamp light pipe to the HD 24. So your microphone preamp becomes the master and you must set the HD 24 to accept ADAT light pipe from your preamp as the master clock. This should provide clean tracks to the HD 24. Can you listen to the HD 24 tracks played back from the analog outputs and see if they contain static? If they have no static, the preamp is properly clocked to the HD 24 or vice versa. But going back from the HD 24 through your preamp to your computer is where all the problem is. And there's no reason to do that so your question is really moot. You're getting static because of improper operational procedures. Sure, you might be able to get it right but there is no point. It's inefficient & problematic. I've been a regular contributor to the HD 24 Yahoo site and only recently pulled away since recording.org takes up enough of my time. Heck I'm not even on the Scully site on Yahoo anymore and I was one of the last knowledgeable Scully employees, QC manager, final test technician so I'm not jerking your chain. I just want to flush the problem out.

TOILETS R US (Testing Of Independent Logistic Transforming Sounds or toilets for short)
Mx. Remy Ann David

This setup should work just fine for transferring digital songs from the HD24XR to your computer as long as you get the clocking right. If you want to use the Presonus as the clock master, I would run BNC clock into the HD24XR from the Presonus. Use 75 Ohm coax from the Presonus word clock out to a 75 Ohm T-piece on the rear of the HD24XR and put a 75 Ohm terminator on the open end of the T-piece. Set the HD24XR clocking to Word. The correct cable impedance and terminator is important, as the HD24XR can be upset by reflected clock pulses.

Using a large buffer size in Sonar and you should be able to transfer up to 24 tracks (3 lightpipes) without pops or glitches.

If you still get pops and clicks in the transferred files, you should diagnose whether they are due to the lightpipe transfer to the Presonus unit, or the FireWire transfer into the PC. You can use the FireStudio software to set the headphone or monitor outputs to check each or a mix of of the lightpipe input channels during the transfer, but just listening to one of them should give you the picture.

I hate to assume so I'm gonna ask. Do you have both input and output connected on the HD24xr? Also, clocksource via adat is set as optical on the HD24. Clocksource via bnc connection is set as word.

The clock should have been set on optical. The "word" option is for the bnc coax only. That would explain why it wasn't synced and drifted in and out.

Does it sound like the kind of random snap and crackle we used to get on a statically charged vinyl LP?

I've experienced a noise just like that 5-10 years ago importing from ADAT into ProTools using lightpipe. Obviously in that case they both had to be set to either 44.1k or 48k. My problem turned out to be which device was designated to be providing the "Internal Clock" and which was designated to run from the "External Clock" provided via lightpipe. It's been quite a while ago, and I wish I could say I remember exactly which combination worked - but as soon as I switched who was in charge of the source clock my 'snaps' went away for good. It was the opposite of what I expected to work - but again fuzzy memories. Sorry about that....

I know you're using a different dedicated recorder and different DAW program, but it's essentially the same set-up.

We are a bunch of mother clockers!

Nice girl
Mx. Remy Ann David

Don't waste your time with the Presonus. Just record to your Alesis HD24. Then transfer your audio files into your Daw. I use the Alesis HD 24 to remote record all the time.
It works great. Been useing one for years.

Bump.

Hey Joel, any more updates on using the Presonus Firestudio Lightpipe with the Alesis HD24XR? Did you fix the problem? I have read several places that the A/D conversion of the XR is top notch. Just curious what your results are after a few months of using it.

I've also had those sounds before and it was always clocking issues. That's amazing that crappy fiber optic cables were making all the fuss! That RME card looks like a beast, but I'm using a Macbook Pro so firewire is what I'm hoping to use.

What fiber optic cables were you using, and what did you switch to?

Thanks for the response Joel!