Optical fiber - laser Vs Diod noise


I have an optical bridge for network noise isolation from 4 years, based on a delock 86443 ethernet/optical media converter supplied (donwstream) by lifepo4 battery (this MFC does not have inner HF voltage regulator and is great with a battery supply).

I have a huge and great impact on the SQ with it in half duplex optical mode / lowest 10Mbs ethernet rate.

I need to connect this downstream delock to a new router with an SFP (optical) slot.

The Delock 100base FX MM 1310nm spécification and i don't find any SFP on this specs for my router (ubiquiti edge router X SFP).

I will probably change the delock it for a Gb one.

I have the choice between SX monomode and multi mode.

Monomode is laser diod, Multi mode is diod. I cannot test each all kind of SFP.
Considering the Laser/diod noise has a strong effect on noise (i can see it using half duplex Vs full duplex), do you know wich one might produce the less noise ?

Thank you

I reply to my own question in case is useful for someone.
I changed my 100mb delock 86443 FX MFC to a delock 86442 1Gb mono mode SX MFC.
The sound is better : narrower and deeper soundstage, better definition.
So less noise than the FX (that was itself much better than the noisy tp link mc110s with its hf switching dc regulator).
Could be several reason but I think this is because of the less power use by diods instead of 83446 laser.
The mfc is supplied by the same lifepo 3,3v batteries.