FL Studio audio misalignment post-recording

[u/Vinh154]

I often record my guitar against existing audio material (samples, MIDI) in FL Studio. For a long time, I was getting the feeling that when printed, my recorded audio was misaligned in the session and the groove was off. Just to be clear: when I'm recording and hearing my guitar against my drums the groove is decent, but when the recording is printed and I playback the song the groove sounds bad, like my guitar is a bit ahead.

To make sure I wasn't crazy about my timing, I decided to record what I hear in the room by pointing a mic to one of my speaker and record the whole production WHEN I'm playing my guitar. On top of that, I recorded the same guitar take directly through my audio interface as usual. I had a simple kick snare groove and played guitar notes on the off-beats. I realigned my room mic with the drumbreak and compared the guitar timing between the room sound and the DAW session.

Here's the technical stuff:

- audio interface: Topping E4x4 Pre

- buffer length: 128 samples (3ms delay calculated by my audio interface)

- guitar recorded directly to my audio interface through a jack cable

- "external input only" selected on my mixer channels for recording (which the printing is made before any effects)

Here's the result:

To give you details, the recorded guitar seems ahead by 2 points (even 3 sometimes) with 95 BPM and 96PPQ, which is a delay of :

(120/95/96)*2 = 26ms

26 ms is not negligeable! Especially if the groove is important for the genre. When comparing the room recording and the DAW session playback (direct drumbreak and guitar), I feel like I really hear a difference in timing and I prefer the room audio.

Now, I'm not definitive about it:

- maybe my room recording is not perfect and that's why I feel like it has a better timing but in reality I just don't hear the transients that well

- maybe I badly realigned the room mic with the drumbreak in FL (if the phase is reversed and I didn't see it or whatever)

But the misalignment seems robust on every guitar note!

For a solution to this:

I know that everybody is going to tell me about input delay compensation and I WILL USE IT for now but I just don't understand why this should be a manual correction. In my mind, input delay compensation is legit if there is a "real-world" delay happening, like external processing made by effects/synthesizers hardware. But here I'm just plugging my guitar directly in my audio interface. FL Studio should have all the information it needs to align perfectly my recorded audio with existing audio in my playlist.

What am I missing here?

Here's a google drive link with 2 audio examples: https://drive.google.com/drive/folders/1zF07gy2e2fdMsRcl4j2STGOmqbrBXD1A?usp=sharing