MOTU M4 & Cubase ... latency make me sick!

I have a lot of problem with The Motu M4 & Cubase Pro 10.5.30… Latency problems
This is what i wrote to MOTU :
Hi ,
I received the M4 december 10 & can’t have it work proberly !
There is more problems in Cubase pro 10.5.30 … i can’t use any vst amp for my guitar or vocal without a lot of latency …
This is impossible to use on created songs (on used tracks)
I made a mistake by selling my SSL2+ !
Yesterday i made a new song just for test (new tracks with input 3) & everything was ok … & this morning i open it to work on it & the latency was on all tracks (used or not) … so i changed the input from the M4 ; In1, In2, In3, In4 with guitar … it’s unusable …latency destroy everything !
It work for a time with a new song & everything is ok … but it seems that if i close the DAW & that i restart this last work, latency return !
So i made some change in Studio parameter ect … the issue is still there !
With the MOTU It’s like something stay on memory and interfered with the proper functioning of audio vst.
Now i’m forced to return to my HD500X with its own sounds.
Last week I made a ticket on this problem …
Something corrupt the files ! (???)
I will try to find a way to purge Cubase or contacting Steinberg !

But what did motu reply? Doesn’t this seem like a driver prob?

Hi Steve,
No answer for now !

A new problem appear with M4 MOTU, now i have feedbacks on my Headphone or monitors when i use input 3-4… the feedback come from the input 2 where my sm7b is connected with gain to zero… the feedback disappear when i put the gain monitor to zero (input) … but now i can even hear my voice or when i type on my keyboard & the gain is at zero !

*mon 3-4 (on) at input monitor mix = no feedbacks … if i increase to playback the feedback is very annoying.

*mon 3-4 (off) at input monitor mix = feedbacks all the way evenif there is no volume it’s a constant feedback (very dangerous for the ears)

My Eris 8 speakers are always closed !.. what is going on ?
I can’t fix Latency & now feedbacks come from the input 2 when input 3-4 are in use !
That is insane !

Oh the feedbacks come from an amp simulator plugin used by the input 3 … but why the vocal was hears ?

hardware monitoring?

While the track input 3 with amp sim for guitar was activated (monitoring) , the microphone from the input 2 was heard … this is not normal !
… and feedbacks …
I sold my SSL2+ & no problem like with it !

The plugin Waves AR Masterring Stereo was in fault.
Used on the Stereo out for a while … to find the problem I had to delete it … disabling it gave nothing!
The problem is resolved !
Thanks !