You are correct Graeme, latency is indeed the word!
The problem is this, lower latency gives you less delay but demands greater computer power, in the limit the sound will start to crackle and cut out but if you have even a passing good computer (less than 4 yrs old say) it should easily cope with the low demands of two tracks at a time.
I note from the manual that the FW solo has ASIO drivers and these are the bizz! When you have a track setup in Silver, hover the mouse
arrow over the centre of the screen and click letter "y" A big box of "stuff" will appear allowing you to set almost everything up. Look near the top for drivers. I think Sam defaults to MME, click the ASIO blob. You will now almost certainly have to set the Solo as the ASIO device. If the delay is still not acceptable look into setting the Solo for a lower latency but if you go too far things will crackup. If you cannot get acceptable latency you might have issues with the PC, but even this is almost always sortable.
Not suprised that mic'ed guitar recording was not
stellar! Not the easiest of tasks, you can find tutorials on the web, notable ones from
Sound On Sound | Recording Techniques | Audio Technology | Music Production | Computer Music | Video Media
Direct in from the guitar is a bit of a puzzle. Is the Fishman an active pickup, i.e. does it use a battery? If so is it a good 'un?! If not you have a passive pup and need a pre amp.
And last thing for now. You should be recording with 24bits and at 44.1kHz and your average levels should be around -20 to-18 on the Silver's meters.
Dave.