A Sound Decision solution
by Kegler
Using VOLUME CONTROL, per 25 Across, ten entries change from one to another of the musical volumes PP, P, F and FF.
Across
| 1 | SPART + A (rev) |
| 6 | BASICS (ABCS IS anag) |
| 12 | TAPER (PRATE anag) |
| 13 | GAPE (PAGE anag) {P->FF} |
| 15 | NOTe |
| 16 | IRREGULAR (rev hidden) |
| 17 | PICK + LE {P->F} |
| 19 | TUFA (hidden) |
| 20 | L(A + H)ORE |
| 22 | C(H)AFED (DECAF anag) {F->PP} |
| 24 | ECHOIC (CHOICE, moving the E) |
| 25 | VOLUME CONTROL |
| 27 | B + AND |
| 29 | SAGE (1st letters) |
| 31 | REF + U + sTATION {F->P} |
| 34 | T(A)R |
| 35 | COR(DONBL)E + U (BLOND anag) |
| 38 | S + HEEP |
| 40 | GOO + D |
| 41 | SNI(P)ER (REINS rev) {P->PP} |
| 42 | OF COURSE (UFO'S CORE anag) {F->FF} |
| 43 | WHEY ("WEIGH" hom) |
|
Down
| 1 | S + TIPPLE {PP->F} |
| 2 | PA + RIAH (HAIR rev) |
| 3 | cREEK |
| 4 | AGUE (hidden) |
| 5 | CALI + CO(C)AT |
| 7 | AFR + O (FAR anag) |
| 8 | SE(A)T |
| 9 | INSU(FFEj)RABLE (jEFF rev) {FF->P} |
| 10 | COPPER (2 defs) {PP->FF} |
| 11 | STRAD + DLE (DARTS rev; LED anag) |
| 14 | FA + S(HI)ON |
| 18 | CHILDPROOF (ORCHID FLOP anag) |
| 21 | RCMP (rev hidden) |
| 23 | PETS (rev) |
| 24 | EU + NU + CH |
| 25 | VER + TIGO (I GOT anag) |
| 26 | H(EAR) OF |
| 27 | BAR + ON |
| 28 | DONS (2 defs) |
| 30 | GREECE (hidden) |
| 32 | TORSO (ROOTS anag) |
| 33 | PUFFY (2 defs) {FF->PP} |
| 36 | O(OP)S |
| 37 | A-I + R |
| 39 | HEW ("HUGH" hom) |
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