Firewire audio issues Mac + Motu

[piffle]

Hi folks,
My first post here, so please be gentle

I am a musician, I run Logic X on a 2008 8 core mac pro with 24Gb RAM.

I have used this system since new in conjunction with a motu 828 mkII interface and have always found it to be a reliable set up.
A few months back I started to, intermittently, get some dreadful popping and crackling noises along with a big drop in sound quality. (This problem only occurred
when using the two front panel xlr inputs.
I did all the usual things to check all my wiring, leads and connections but the problem continued. I took my collection of mics to a friends studio and checked
that they all worked correctly. Having established that the mics were ok i started to entertain the possibility that my interface was on its last legs. I bit the bullet
and bought a new focusrite saffire pro 24 only to find that the problem has not gone away. So to my question; Is it possible that the firewire bus on my mac is causing this and if so
is there a chance this could be rectified by installing a pci firewire card in my mac to use instead of the built in ports.
I know my mac is getting a bit long in the tooth but a replacement is out of the question at the moment so any advice or thoughts on this would be gratefully received.

Thanks guys

 

[chscag]

Welcome to the forums.

You are not going to get an answer without providing information. We have no idea which Mac you have (year and model) or what version of OS X it's running?

 

[jacksutton809]

Hi piffle, what buffer size are you using in your DAW? Pops, clicks, and crackles are quite often to do with the buffer size being too low. Basically that means the audio engine doesn't have enough processing time. That would explain why changing the audio interface didn't make a difference (the MOTU and Focusrite models you mentioned are similar spec if I remember right...), assuming you were using the same computer and DAW?
Have you tried any other firewire devices to test out the port? I'm not really sure how likely it is that the firewire bus is the problem.

 

[piffle]

I use 2 x Quad core 2.8Ghz mac pro 3.1 with 24Gb Ram. OSX 10.10.5. Logic X is my main music software.
Had tried to enter this info on my profile but it doesn't seem to want to update.

 

[piffle]

Yay .. updated ... maybe my painfully slow broadband.

 

[jacksutton809]

What's your buffer size set at now? Always worth checking!

 

[piffle]

Buffer is set at 256 - which is the setting i have used since i got this mac.