The instruments are a bit off starting with the second loop

[RetingencyPlan]

So, after playing the first loop(a.k.a. the first 4 minutes) the instruments start sounding a bit off...
Maybe ridgerac2 has this only issue but it could be evident in others as well...
ridgera2_051.zip

[superctr]

it's a problem in the original sound data. see notes