renderAnswer _ db (src, dur) _ = buildSynth $ do
  let env = maybe (return EmptyGraph) (unitRectEnv (Millis 1)) dur
  synthSource src >> gain (Db $ -10) >> env >> destination
  maybeDelete (fmap (+Sec 0.2) dur)
renderAnswer _ db (src, dur) _ = buildSynth $ do
  let env = maybe (return EmptyGraph) (unitRectEnv (Millis 1)) dur
  synthSource src >> gain (Db $ -10) >> env >> destination
  maybeDelete (fmap (+Sec 0.2) dur)
renderAnswer _ db (src, dur) _ = buildSynth $ do
  let env = maybe (return EmptyGraph) (unitRectEnv (Millis 1)) dur
  synthSource src >> gain (Db $ -10) >> env >> destination
  maybeDelete (fmap (+Sec 0.2) dur)