Hello, when playing in wave survival mode, I have noticed that when ever in between waves when I want to build more units or bunkers and I press space, then finish building, units or systems will randomly just break/die/turn to dust. I havent really figured out what exactly is the reasoning, but my first guess would be something with limiting the amount of units on the field.

Sounds like you're exceeding the MOID limit. If there's too many objects in the level at once, it'll cull some until it's back within the limit. It happens a lot in Wave Survival, unfortunately.

It's the same reason Crab Bombs were a thing.

Okay well that sounds like it. Is there any way to increase the limit. I imagine my PC can handle it. Its an 8core amd top of the line.

It's a hardcoded limit, MOIDs (the IDs for all moving components like MOSRotatings and whatnot) are encoded as a byte which has only 256 unique values so when there are more than 256 MOIDs things get weird.
There's been discussion of changing the way MOIDs are encoded but I don't think anything came of it so far. Any improvements would require engine changes, so that's all on Data.

its really annoying if you use skeleton labor they tend to break along with what you mention systems and such but being so cheap it isn't really a problem..

well Im starting to think this isnt the case of what is happening to me. Mainly because I have never noticed a unit suddenly disappear by its self. It only seems to happen at the start of a wave and only in wave mode.

the only bug that i've notice in that mode is unable to pass to the next wave on nuts, which reminds me before anyone asks i was on campaign mode with the same bug when loading a pre build base

Unfortunately, this is a feature and not a bug. For technical reasons (that Dhu102 explaned) there is a limit to many units can be active at the same time, and if that limit is reached objects start to randomly gib.

At the moment the only way to enforce the limit is to kill a few defenders so there is room for the attacking team to spawn units. You do get a gold refund though. This only happens in Campaign mode and Wave Defense btw.