unreliable, (to working)

[RJH_MUSIC]

Sorry seeing this so late it's been a while since I've been on the forum. I share your pain in the troubles with the D8B and have experienced everything you're talking about. 1st the D8B will absolutely not lock to external sync it relies on the internal clock card and it must be turned on and booted up before you turn anything else on in your studio so that it won't conflict with other sync Devices. I have also had to replace clock cards frequently as they also go bad. When you turn the unit on, it goes through the motions and at some point the rude solo light will blink. Just before it is fully booted, all the meters will flash, and the faders will snap to last position and the rude solo light goes out. If during startup your meters do not flash and the rude solo light remains flashing that might indicate a bad clock card. In addition if a clock card is bad, you may see audio drop out on several or all channels.

Next problem which is the most common problem. You mentioned the thermal issue and I agree if your D8B boots up and will work for 15 or 20 minutes before everything goes haywire and lights stick on or then go off, console freezes and then the root solo light stays on that means your 5 volt power supply is bad. That is the LPS 152 power supply in the CPU that stands upright. I have 2D8B and I have replaced both of mine at least 5 times in the last 2 years. They are found on the internet now and then but not cheap. I took an alternate route and rebuilt custom cpu with all new power supplies.

[Y-my-R]

Thanks very much, RJH_MUSIC!

Since I have a spare rack unit that generally works (aka the power supply issue), I connected that yesterday morning, after my "daily driver" rack unit already gave me issues with a S/PDIF export about 20 minutes after turning everything on.

It booted up with that unit without getting any meters stuck at the moment you're describing (right after rude solo goes off), and then continued to work without issues for the whole day.
I turned it on again a little while ago, today, and again, no stuck meters and it just started working as it should.

So, I think you hit the nail on the head, with calling out the 5V power supply. In my case, it seems that this is responsible for all the issues I was seeing... I didn't replace the clock card, but the stuck meters didn't happen after replacing the power supply. But I'll keep the Clock Card issues you described in mind and will try that, too, if I run into issues like that again.

Quick backstory on what I've lately been using as my "daily driver" vs the backup unit, that worked fine since yesterday:
In some older posts, I was exploring to use a 50 foot umbilical cord, and tried different power supply component combinations, finding that only one set of components (generally the newest of the bunch) was able to even allow clocking the D8B to external clock with that long cable. However, the clock would deteriorate quickly, so it didn't "really" work.

Regardless, I knew that this was the "best" of the 3 D8B rack units I had at the time... new type mainboard, and PSU components that "almost" work with the long BFC cable (the other 2 just made the console pulse/thump with the long cable... it wouldn't even turn on).

Some months ago, I was given a 4th rack unit, and to test it, I just started using that as the main one, since my #1 was now sitting in the machine closet - but the standard BFC cable doesn't reach there, unless it goes right across the hallway.

Seemed to work fine... until I started having those stuck meters, and garbled S/PDIF exports followed by thumping on restart.
I guess that I might have caused the damage myself and the power supply component may have overheated. To reduce the noise of the power supply, I had replaced the fan inside the AT power supply with a quieter one, and also throttled the speed somewhat... I used my own (apparently not so) good judgement how much airflow should still be acceptable... but probably misjudged.

Anyway... I'm back up and running, albeit with a (standard length) BFC cable going across the floor and into the machine closet. Looks terrible, but works and is quiet.
Thanks so much again, RJH_MUSIC, and be careful, everyone, with running your D8B with quieter fans... or at least don't throttle the speed like I did (I am a "Volltrottel" in my native language, which doesn't really translate to "Full Throttle" but that'll still be my takeaway for this, hahaha).

Not sure if my issue may be what Phantomrage is seeing or not... so, in my case, it was definitely power supply components (and likely the 5V RJH called out), and not a problem with the console, as it seems.

[phantomrage]

I have not had the chance to fully open and clean/re seat everything. I noticed today I had to re seat the clock card for it to even boot the hardware, and it software side always works regardless...

When it does go down. It is now the same thing. All lights on the board turn off, the rude solo light lights solid red, and the VFD stays lit with the last thing is was displaying. Other than that, audio and the software work fine.

So in hopes today I can pull this apart and start cleaning and re seating all connections.

[phantomrage]

Well......... Shoot.....

Pretty much confirmed internal connection issue... Went to move stuff around and bumped the console..

It's working now, stable for the moment....

I will open her up and perform surgery and clean and re connect stuff...

[phantomrage]

As many have mentioned in this forum and thread, connection, connection...

Seems with my case and I would guess a lot of people. Connections are the one and main reason this board fails. Not including component failure, bad caps, etc..

And there are a LOT of those connections to be made. I know Mackie went with cost savings, but some of the ribbon cables do not seem to be the best choice for the job... Maybe that was the standard type of inter connecting cable to use at the time? Yet computers use them without constant failures.

So is it the metal on the pins causing the issues? When I worked for Nortel, we had a issue with a production run and the pins on the back plane would develop tiny slivers of tin. We had to go into the switch and more or less vacuum the slivers off the back plane to keep it from shorting itself out. Could the pins be chemically changing and that is altering the connection to make or break?

I know my board was not treated well in its lifetime. I found it at a outdoor swap meet and it had sat in the same area for a few months before I could talk the guy down. Outside in the elements. Not to mention how it even got there, let alone its life prior to the swap meet. But it works, and does so very well, when I don't have connection issues. So there is hope for all the consoles out in the wild. Don't lose hope, and sometimes even in the most frustrating of times, it is a simple issue overlooked. (like my tank-less hot water heater, that's a whole different story of money down the drain)

One thing that I have noticed. The heartbeat of the console is the clock card, and if any of those boards lose clock through one of the ribbon cables it is game over. As my connection problem started developing the power up cycle channel click became worse. Now, when I power up the board does not "click" or flash meter lights.