Playing back a bass track (soft synth midi) in solo creates lag and dropouts...

 
Does this happen to anyone ?
 
Now say I have a number of tracks of different soft synths including a track for bass guitar (SI-Bass say). When I solo the bass track to listen to it for applying EQ or other things, it plays back with a lag and sometimes even drop-outs occur. The interesting part is that there is no problem when it plays along with all the other tracks. Its only when its played back in solo mode. In fact, the same lag or drop-outs also seem to happen when I play the bass track within my step sequencer (by clicking the play button within the step sequencer) which of course plays as solo even without solo-ing the track. But there is no problem once again when I play the whole project by pressing space bar.
 
What could be the problem ?
 

 
 

dcumpian
I can't imagine what the cause could be. I solo stuff all the time and have never run into anything like this. When you solo the track, are you enabling anything else, like a plugin perhaps?
 
Regards,
Dan
 

Nothing really of that sort. I don't enable anything in particular when I solo the bass track. Whatever is already there, is there. And to clarify again, this problem is only when I solo a bass track (I guess I should recheck if this is anything to do with SI-Bass guitar soft synth in particular and not others). I solo other tracks at will, and there's no problem.
 
It'll be very helpful if someone could check if they could reproduce this when solo-ing a bass track, in particular trying out SI-Bass guitar. Meanwhile, I'll check if this happens for me only with SI-Bass or a bass guitar patch in any other soft synth.

A couple of thoughts:
 
Like many bass synths, SI Bass is transposed up an octave so you can more easily perform bass parts on a 61-key keyboard without transposing the keyboard. This means that parts played in a normal range (e.g. 3rd-party MIDI clips intended for GM synths) may go below the range that SI Bass can play, resulting in missing notes. Try transposing the track up 12 half-steps using the Key+ (Key Offset) setting in the Inspector for the MIDI track (or MIDI tab of an Instrument track).
 
In trying to replicate a problem I found that many patches SI Bass patches (especially muted patches like 'Picked Mutes') have a really odd/variable attack that can make the timing of some patterns sound really wonky. Try the 'NiceBass' patch as reference; this one sounded fine to me with once the part was transposed up.
 
Both of the above issues are somewhat more obvious when the track is soloed.