Mathematica code doesn't work when using version 9 - wolfram-mathematica

Question

I have written the following code which works ok in Mathematica 8. However, when I open the very same notebook in Mathematica 9, the following message arises: "InterpolatingFunction::dmval: "Input value {0.000408163} lies outside the range of data in the interpolating function. Extrapolation will be used. ", and there is no graph.
Here's the code:
Manipulate[
ParametricPlot[
Evaluate[{x1[t], a YP[[2]]/YP[[1]] x1[t] + (1 - a) YP[[2]] x3[t]} /.
Quiet#NDSolve[
{x1'[t] == x2[t],
x2'[t] == -1/
Mass (c x2[t] +
a YP[[2]]/YP[[1]] x1[t] + (1 - a) YP[[2]] x3[t] -
Fmax Sin[(2 π)/T t]),
x3'[t] ==
x2[t]/YP[[
1]] (1 - Abs[x3[t]]^n (γ Sign[x2[t] x3[t]] + (1 - γ))),
x1[0] == 0,
x2[0] == 0,
x3[0] == 0},
{x1[t], x2[t], x3[t]},
{t, 0, tTotal}]],
{t, 0, tTotal},
ImageSize -> {450, 450}, PlotRange -> 10, AxesLabel -> {"u", "F"}],
{{tTotal, 20, "Total time"}, 0.5, 100, Appearance -> "Labeled"},
{{Mass, 2.86, "m"}, 0.1, 10, 0.01, Appearance -> "Labeled"},
{{T, 4.0, "T"}, 0.1, 10, 0.01, Appearance -> "Labeled"},
{{Fmax, 8.0, "Fmax"}, 0.1, 10, 0.01, Appearance -> "Labeled"},
{{n, 2.0, "n"}, 0.1, 10, 0.01, Appearance -> "Labeled"},
{{c, 0.0, "c"}, 0.0, 10, 0.01, Appearance -> "Labeled"},
{{a, 0.05, "a"}, 0.0, 1, 0.01, Appearance -> "Labeled"},
{{γ, 0.5, "γ"}, 0.01, 1, 0.01, Appearance -> "Labeled"},
{{YP, {0.111, 2.86}}, {0, 0}, {10, 10}, Locator}]
Any ideas?
TIA

Answer 1

Summarising the problem. This works in version 7 & 8 but fails in version 9:-
tTotal = 20; Mass = 2.86; T = 4.0;
Fmax = 8.0; n = 2.0; c = 0.0; a = 0.05;
\[Gamma] = 0.5; YP = {0.111, 2.86};
NDSolve[{x1'[t] == x2[t],
x2'[t] == -1/Mass (c x2[t] + a YP[[2]]/YP[[1]] x1[t] +
(1 - a) 2.86 x3[t] - Fmax Sin[(2 \[Pi])/4.0 t]),
x3'[t] == x2[t]/0.111 (1 -
Abs[x3[t]]^2.0 (\[Gamma] Sign[x2[t] x3[t]] + (1 - \[Gamma]))),
x1[0] == 0, x2[0] == 0, x3[0] == 0},
{x1[t], x2[t], x3[t]}, {t, 0, 20}]
Use a more specific method in version 9.
NDSolve[... , Method -> {"DiscontinuityProcessing" -> False}]