Based on a suggestion in the Mixing Audio book (Focus Press) I just tested my listening position for early reflections by playing a 1khz tone alternating between left & right. Initially, the sound seemed to be pretty much coming from the centre all the time :o with a level drop on the left.
When I placed a blanket over my console the problem was substantially fixed.
Obviously I can't mix like that, so what can I do ? I already have 6 foam tiles opposite my ears on each side wall, and on the ceiling, but anyway this seems to be console reflections.
Assuming all early reflections from nearby walls/ceiling have been dealt with; increasing the distance between the speaker and desk, raising the speakers (and if so, a slight tilt so the acoustic axis is still pointing towards the ears), minimizing the desk size and also tilting it, redirecting the reflection away from head height, are some measures one can do to minimize these early reflections.
The first "glob" at 1-2 ms is probably the desk and the one at 4 ms might be, that one is about 1,3 meters longer than the direct signal from the monitors. Can you move the speakers a bit further away from the desk? This might get the reflections to pass by you below ear level.
Try reversing the phase of one speaker. Play Pink Noise. Listen for a null at the acoustic centre. It can be helpful to block one ear and listen with the other. The null is usually very precisely placed. It may not be where you expect it geometrically. If you have desk reflections causing problems, they can be seen as spikes on the ETC or quite vivid comb filtering. Chose your view. Either way the problem is fairly easily diminished by moving the speakers or angling the desk. Desktop Reflection Revealed