Hello,

i just upgraded an old mac pro 5.1 to mojave after changing the gpu.. Than the trouble with the ff400 started.. it needed a lot of reinstall to  make the rme drivers connect to the ff400 again..

It turned out that i couldnt do a clean install of mojave..had to install high sierra and rme drivers first..and update sierrra than with mojave..to make it work.. This run i had to make two times..on my test install..and on my main disk... So sofar it looked like a driver install issue on the actual mojave download.. or a genaral thing that you cant do a clean install of mojave but have to step up from sierra to take your drivers with you.. really? anybody heard such a thing?

So it did for a while, hours.... but from time to time the interface lost contact..repowering it caused a reconnect..going back to a high sierry partition worked more stable... at least it seemed so..

Until than it all looked like driver problem... but..now the ff400 has stopped to connect at all.. it behaves ok..is alive..tries to connect.. but nothing.. and that also on another computer ..so its not the mac pros fireface connection..

seems the ff400 died..  All  just by accident now..temps go up in the room?? summer is coming?

Or are there problems with the latest mojave? and all the installation stress caused addidional hardware issues?
Good question to decide which direction to go.. 

why has the interface reacted first more picky on mojave before it died?
or is this again just a false conclusion and its just increasing drop outs while doing installation work..and this all would have happened on the old high sierra install too?

and i got fooled and installed everything 3 times?  So if the ff400 just dies on warm weather and age..and its just the firewire connection.. Is there a speicail chip that is known to die eraly on this machine i could replace? i can do smd soldering..

and corona makes id difficult to think about a new interface... changing the firewire chip as a shot in the dark? or should i look at some other candidates ?

thanks for any input or reports of simmilar phenomenons some might had in the past..and how they might have curred the problem..
greets