HELP!! GE Tumble Dryer – intermittent scraping noise

Model No. DISQ493DT

I have a General Electric large capacity tumble dryer – the american style.

After lying dormant while we were on holiday, the tumble dryer now has a scraping noise when we use it. There’s a dull, rhythmic (for the want of a better description) scraping noise as the drum turns. To confuse matters, the problem comes and goes, it sounds normal for a while, seems to have cured itself, then the noise comes back again. Everything else is okay, good heat, fast dry etc, just this intermittent scraping noise.

Any ideas what it is? Is it something we can fix ourselves, or is time to call in the boys?

I have posted this problem twice but have got no posts back. One last ditch attempt before I call in the engineer!

Thanks.