How do I solve 1 across in Daily Telegraph Cryptic 31258?

Question

Accepted Answer

1 across reads "Checks digestive issue – without question these things are a let-down" (4,6 letters); the answer is DAMP SQUIBS. It's a charade: the answer breaks into parts in clue order, each part clued by a word or short phrase. No indicators needed; watch for standard abbreviations (RA = artist, US = American, IN = at home) and short synonyms. The full step-by-step breakdown is on this page.

Checks digestive issue – without question these things are a let-down (4,6)

1A — Checks digestive issue – without question these things are a let-down (4,6) — DAMP SQUIBS