Fireface 800

RME Fireface 800 is a high quality firewire audio interface. I have repaired several of these units. They all have a mix of good quality and low quality capacitors, but it's hard to predict where the bad ones are, as this varies between production runs. Your best bet is to check all capacitors with an ESR meter (in circuit) and replace those where you see variation in ESR for the same value component. On most of these boards that I've come across I've ended up replacing ALL surface mount electrolytics and the majority of the leaded electrolytics. Beware: you need a good quality soldering iron for this one. This is a lead-free board, the traces are very fragile and the holes for component legs are very tight. You are almost certain to ruin a few traces, so be prepared to do some bodge repairs.

Problem	Solution
Defective power supply. Dead unit or instability.	All the units I have come across have had the PSU replaced with a new replacement from RME. I have not yet had the chance to repair a faulty PSU on these. Someone else will have to chime in on this one. New replacement power supplies are still available from the dealer (at least they were still available in 2020).
Loss of volume on output channel(s)	replace the 16 capacitors near the output jacks
Malfunctioning inputs or preamps	Replace capacitors in the area. If your problem is around the rear inputs, do all capacitors near the rear inputs. If your problem is near the preamps or instrument inputs, do the capacitors in that area. To replace the surface mount capacitor by instrument input 1, you have to take off the front panel. Only way to gain access is by desoldering all 4 XLR connectors at the front panel.
There are 3 firewire ports on the back. A lot of cards have 1, 2 or 3 failed ports.	Someone else will have to chime in on this one, I have not looked into this issue

Credit

Original article credit: AMelbye