Audio Problems In Studiovision 3.5/powermac 85, Audio files suddenly play at max level Options

[SwedishGuy]

Oldie question, vintage software:
I'm using Studio Vision 3.5 on a powerMac 8500 since a couple of years. Works fine as a musical sketchbook for me.

But over the last 6-7 months, strange things have been happening with the audio tracks and/or the AIFF files that I place in these tracks.

Strange thing 1: after 2-3 hours into a session, audio files will sometimes lose their level settings and start blasting at full level. I use the "console" as a mixer to set audio levels for various vocal parts but then suddenly some of these files will - regardless of volume setting - scream away at top volume (not fun when I'm using earphones). Dragging the volume slider on the console for the misbehaving file has no effect (although it worked earlier in the session).

Strange thing 2: on opening a sequence that was fine yesterday, Vision will suddenly complain "the audio file xxxxx.aif is too short. Shorten the events to fit the length of the file ?"
although the file is OK when played in other sound programmes. This also happens after 2-3 hours into a session

This never happened before. Could it be a computer fault, maybe my 8500 is simply overheating after a while ?

I could move the whole setup to my adb G4 but need it at the other end as the final recording mixdown platform for the tracks outputted from the 8500.

Any ideas ?

Thanks in advance
Swedish guy