Disappointing when it once but a few sheets are more

For several weeks, the paper shredder with us now in use and I am increasingly disappointed. While he initially seemed good on the ball and the leaves at least shredderte quickly, he breaks down increasingly.
Meanwhile, he shreds single sheet of paper only a snail's pace, the power of the engine seems simply too weak.
Go 5 sheets of paper at a time, but if there are maybe 15 or 20 sheets of paper, which in turn whether individually or stacks are shredded to three leaf, he comes arg stumble. After about 30 sheets of A4, individually, it shuts down and does not do anything more, he probably overheated, the airing seems constructionally bad solved. Then it takes about 15 minutes, until it is ready for use again. The problem it seems grds. with other devices to give, so I had first taken it with serenity.
The performance, however, has now been greatly reduced but he is unusable partly after 7-10 leaf, apart from the now now rather slow speed shredder from the first sheet. Or in some cases long strips came out already and there was no longer the particle section, as always come out on top.
So if you have really rarely to shred something, maybe not more than 5 sheets in the week, for the likes of the shredder be suitable. All others should choose another device, for the price you can not expect much.