This copy machine jams too frequently.

このコピー機は頻繁に壊れる。 This copy machine jams frequently.
このコピー機はよく壊れる。 This copy machine jams frequently.


Jamming the copy machine is very embarrassing, but the speakers in these example sentences are calm. It doesn’t express any irritation.

このコピー機はすぐに壊れる。 This copy machine jams frequently.

This sentence can imply irritation of the user, but it doesn’t clearly say “too frequent.” 

このコピー機は壊れる頻度が高すぎる。 The frequency that this copy machine jams is too high.

This sentence clearly states that the frequency is too high but sounds unnatural. So, I would recommend the following complaint:

このコピー機は壊れてばかりいる。 This copy machine jams too frequently.

Tips on Japanese (Website) http://www7b.biglobe.ne.jp/~meadowlake/adverbs.html