Leave a firewire device plugged in when not in use?

[danhaun]

I use Canopus (Grass Valley) ADVC-55 video converters to digitize the output of some vintage but high quality microscope cameras with great results. For some practical reasons beyond cost, these out perform available digital cameras.  The problem is that these converters are Firewire devices designed to convert VHS tape to digital, they  are no longer produced or supported. I would like to keep them operational for as long as possible.  I have two working ones and two that were working but then suddenly stopped converting. I usually keep them plugged in to the computer all of time. I've done this for 11 years to one box that recently quit on me, so I am now questioning that practice. One of the functional boxes seems to want to warm up before it will convert video andI am wondering if this is sign that it too will fail.  Two of the large chips on the board are very warm to the touch even when not converting video.  I have-read on line about failing capacitors over time and wonder if it better to remove the power source.

My question: Should I unplug when not in use? Is there anything else I should be doing to make them last? and finally What about repair options? Should I consider this or instead try to buy up a few more spares on eBay? Would that even help if components fail over time?

Sorry if this are dumb questions. My expertise is in laboratory science. Thanks in advance for any advice.

[Faranight]

I'm not sure about Firewire, but I learned a lot about failed components and repairs from watching this guy on youtube.
Here's a video how he finds and replaces failed caps on laptop motherboards:
Things are definitely fixable. If you have a donor board you can desolder some spare parts and replace the failed ones on another board.