Yes, that is quite possible, because the fade time in standard synths is very short (to keep the general feel crispy). You could try to write # legato 1.1 - is that better?

Nope, I tried 1.1, 1.01, 1.001 and other values. Maybe the only solution could be to elaborate an algorithm which makes the audio buffer continuous..becouse something is restarting when a cycle ends and the next starts...that gap should be filled, or maybe a fade effect that smooths the end with the start. I think this isn't an urgent issue..becouse while music is playing the glitch is inaudible..but it would be nice to have a fix. Maybe I could help but I don't know where to look at.

Could you try # fadeTime 0.2 ?

I did:
d1 $ s "in" # fadeTime 0.2

I got:

tidal> d1 $ s "in" # fadeTime 0.2 

<interactive>:19:15: error:
    Variable not in scope: fadeTime :: Double -> Pattern ControlMap

Also I can't find fadeTime keyword in the documentation..did I do something wrong? I'm a beginner.

Ah sorry, I didn't know it wasn't added to the tidal side (I can't try right now). If I remember correctly, it was in tidal:

let fadeTime = pF "fadeTime"

@yaxu shouldn't we add that?

you could try this.
Otherwise, in supercollider:

~dirt.orbits[0].set(\fadeTime, 0.1)

But then this is global, and all the sounds will be "softened".

Ok I made some test using the first option by putting let fadeTime = pF "fadeTime" in my Tidal.ghci in vim plugin, now it works..but it is like a fade out and still gives "digital kisses"..I did try negative values also. Better without it.

Ah now I understand why this is. Other synths have their own envelope for the attack section, but the input synths don't have this.

Forget about the fadeIn, just run this in sclang:

// live audio input
(
SynthDef(\in, { |out, sustain = 1, pan, inputFadeTime = 0.03|
	var env, sound;
	env = Env.linen(inputFadeTime, sustain - (2 * inputFadeTime), inputFadeTime).kr;
	sound = SoundIn.ar([0, 1]); // stereo in
	sound = sound * env;
	OffsetOut.ar(out,
		DirtPan.ar(sound, ~dirt.numChannels, pan)
	)
}).add
);

I'll correct the source as well. You can adjust the crossfade, if you add to tidal:
let inputFadeTime = pF "inputFadeTime", and then # inputFadeTime 0.02 or so...

I made an issue on the tidal repo for the missing parameter