malloc() errors and screen freezing

[shinyzin]

I don't know when it started, but my server is dying due to malloc. Some days it closes once, other days three times, sometimes consecutively, sometimes not. I really need to solve this problem because my players are suffering from rollbacks every time the server closes.
No modules used, no excessive RAM usage, we're confused.
The errors I received when the screen freezes were:

malloc_consolidate(): invalid chunk size
double free or corruption (fasttop)
malloc_consolidate(): unaligned fastbin chunk detected
Segmentation fault (core dumped)
malloc(): mismatching next->prev_size (unsorted)
malloc(): unsorted double linked list corrupted
malloc(): unaligned tcache chunk detected

Thank you in advance.