First post here for me 
I got my A4 about a week ago and I must say I am really pleased with it.
While playing about and editing a sound today I noticed small popping sounds mixed in from somewhere.
I’m not sure if this was due to something I connected to a lfo…
Anyone have any idea what this is?
Did you have the sequencer playing with some trigs on the track you were editing? I find I get small pops expecially when messing with the filters on a drum track. Reason behind this is the machine has to quickly revert to the locked sound and can cause minor clipping at times.
Or maybe some parameters got changed, hard to tell with no audio example.
I’ve found several cases where popping and other artifacts may appear.
Sounds that end too soon and abruptly may cause this. As VanillaSun said sound locks are one reason. Polyphony settings and voices resetting may cause this too.
Another reason are lfos peaking as you suspected, and fx tails. With the fx you can notice it when changing patterns specially.
If you were exploring wildly with the sound I’d bet you set something extreme somewhere in an envelope or lfo and that’s all.
Have fun with your A4! 
It’s my understanding that short pop sounds are actually clipping somewhere in the signal path.
The first thing to do is to check the Envelope -release settings ( most important the amp - env. ). when clicking > check if thy are not at 0 ? > if so, add a minimum - value until the Clicks disappear, most of the time value 1 will be enough… if this dousn’t help you can rule those out and dig deeper > but 9 on 10 that will be the reason. ( sometimes adjusting the Env. attack - fase can help - or by eliminating the attack - fase by using non-retriggered Envelops = not dotted )
Sometimes a specific click can be annulated by tying steps together = by a parameter - glide > but this can alter the sound drastically.