Inconsistent Bubble Generation for Magma Blocks

When i do look at the normal generation of MagmaBlocks inside sea , into ravines or ruins, the natural bubble Generation from each block is inconsistent. On my video many Blocks are not giving bubbles off, till i have to update them putting blocks nearly, breaking seagrass, or just waiting after some minutes to see the bubbles.

Visual Evidence:

https://www.youtube.com/watch?v=0SXTv9DD7Yo