Crossing spokes pressing against each other is beneficial for tension change compensation when using disc brakes or pedalling. The only way to avoid rub that I can think of is to lace the wheels without spokes interlacing at the crossing (i.e. without the spoke exiting hub flange outwards being laced under the last spoke it crosses).
A way to reduce the rubbing noise:
- Well-tensioned spokes (the lower the tension, the more likely are the spokes to make the rubbing noise at the crossing).
- A bit of lube at the crossing ("flossing" the crossing with some waxed dental floss can do the job without attracting much dust and dirt as oil or a drop of wax could do).
I haven't seen spokes break at the crossing point (at least not...