Post a picture and I'll give some further advice

Sounds to me like the cabinet is not fixed securely.

Movement is what causes cracks in silicone sealant.

Sounds like it needs maybe an L bracket or two, then re silicone

I commend you for spinning vinyl though....

Unfortunately for you, it is extremely likely.

First line, from the first website found on Google.........

What is Asbestos Pipe Insulation and Lagging?

Asbestos pipe insulation and lagging can be one of the most dangerous forms of asbestos.

So whatever gives you such confidence that it is "not at all likely"?

Asbestosis will soon be your friend