With the help of NDSolve I try to solve a very simple BVP:

$Av''(t)+Bv(t)=f(t),$

where A, B are 5x5 constant matrices, f(t) — 5-dimentional vector with components composing of InterpolatingFunction(s). Each component of solution should satisfy:

$v_i(0)=1,\ \ v_i(1)=0.$

The system is enough "good" for solving, matrices A,B are not singular, but I get strange error:

Moreover, last error (NDSolve::bvaux) cannot be found anywhere!

Any suggestions are welcomed. The code is below and A, B, Cv in attachment.

NDSolve[{A[[1, 1]] v1''[t] + A[[1, 2]] v2''[t] + A[[1, 3]] v3''[t] + 
    A[[1, 4]] v4''[t] + A[[1, 5]] v5''[t] + B[[1, 1]] v1[t] + 
    B[[1, 2]] v2[t] + B[[1, 3]] v3[t] + B[[1, 4]] v4[t] + 
    B[[1, 5]] v5[t] == Cv[[1]], 
  A[[2, 1]] v1''[t] + A[[2, 2]] v2''[t] + A[[2, 3]] v3''[t] + 
    A[[2, 4]] v4''[t] + A[[2, 5]] v5''[t] + B[[2, 1]] v1[t] + 
    B[[2, 2]] v2[t] + B[[2, 3]] v3[t] + B[[2, 4]] v4[t] + 
    B[[2, 5]] v5[t] == Cv[[2]],
  A[[3, 1]] v1''[t] + A[[3, 2]] v2''[t] + A[[3, 3]] v3''[t] + 
    A[[3, 4]] v4''[t] + A[[3, 5]] v5''[t] + B[[3, 1]] v1[t] + 
    B[[3, 2]] v2[t] + B[[3, 3]] v3[t] + B[[3, 4]] v4[t] + 
    B[[3, 5]] v5[t] == Cv[[3]], 
  A[[4, 1]] v1''[t] + A[[4, 2]] v2''[t] + A[[4, 3]] v3''[t] + 
    A[[4, 4]] v4''[t] + A[[4, 5]] v5''[t] + B[[4, 1]] v1[t] + 
    B[[4, 2]] v2[t] + B[[4, 3]] v3[t] + B[[4, 4]] v4[t] + 
    B[[4, 5]] v5[t] == Cv[[4]],
  A[[5, 1]] v1''[t] + A[[5, 2]] v2''[t] + A[[5, 3]] v3''[t] + 
    A[[5, 4]] v4''[t] + A[[5, 5]] v5''[t] + B[[5, 1]] v1[t] + 
    B[[5, 2]] v2[t] + B[[5, 3]] v3[t] + B[[5, 4]] v4[t] + 
    B[[5, 5]] v5[t] == Cv[[5]], v1[0]  ==  1, v1[1] == 0, 
  v2[0]  == 1, v2[1] == 0, v3[0]  == 1, v3[1] == 0, v4[0]  == 1, 
  v4[1] == 0, v5[0]  == 1, v5[1] == 0}, {v1[t], v2[t], v3[t], v4[t], 
  v5[t]}, t, WorkingPrecision -> 50, 
 Method -> {"Chasing", Method -> "StiffnessSwitching"}, 
 MaxSteps -> Infinity]