Not enough to do

[MikeUniformMike]

I started a new position a few weeks ago. I am still in my probabtionary period.
The job is fine but I just don't have enough to do.
I am waiting for work from other people as I am the last in the chain for it.
There is stuff that I could do if I had input from others but I get no response to my e-mails, call and skype.
I feel that I am producing very little and my confidence is taking a nosedive.
I have no doubt that I could be very busy if I could get on with the work.
I have already spoken to my line manager.
Any advice?
I want to increase the flow of work without making it too obvious that I am just spending my time looking for some way of making myself useful.

There been a few threads like this recently!! It can be crap at the start if you don't get a proper induction. I also find part of the problem can be the manager doesn't actually know what they are ant you to do.

A reply! Thank you. I've spent today doing the scrabbling around again. It's making me miserable.
The managers are lovely but they are just senior people not people managers.
I try to word my requests so that I'm not actually saying I've got next to nothing to do.
I'll look for the other threads.

Can you:
Ask to shadow someone?
Find a project / see a gap?

What sort of job / company is it?

Thanks for posting.
I have a niche role. There is very little information on anything, and lots of projects where the information is inside people's heads and they don't have the time to spend with me.
It's an R&D type environment.
I work from home mostly.
I have tried to do things off my own bat and forwarded them but got no response.
I have volunteered my ' expertise ' to likely colleagues.

The job is convenient, decently paid and if I was busy, would be great.
Part of the problem is I've started to think I must have missed something and will get fired. I feel like I'm producing nothing.

I could easily spend the time learning new skills that could be useful, but that wouldn't resolve the feeling of not producing anything.

It's a smallish privately owned company with no HR.