Firewire pops, crackles, and poor sound

Hi guys,

I have a 2008 mac pro 24Gb RAM (2x Quad Core 2.8Ghz) which i use in conjunction with a motu 828mk II.

This set up has served me well over the years but i have recently been getting a lot of popping and crackle

on recordings along with an intermittent but very noticeable drop in audio quality. I have done all the usual,

changed cables, reinstalled software, reset pram, tested mic's at a colleagues studio and so on. Having done

all this i decided it was time to bite the bullet and buy a new interface. Enter a new focusrite pro 24 but to my

dismay and frustration the problem is still there.

I've used mac's since 1998 but still really have almost no technical knowledge about how they work,

just that, until now, they just do. Anyway, despite my mac being a bit long in the tooth a replacement at this time

is really not on the cards. I've seen pci firewire cards that are mac compatible .. does anyone know if these

tap in to the macs fw bus or are they independent ? If they are independent Is there a chance one may solve

the problem. Any thoughts on a possible cure for this problem gratefully received.

Just mentioning that there doesn't appear to be any issue with playback .. i tunes etc all work fine through

the same interface

Thanks people 😉