[bug] sound sometimes does not work

Both in sentence view and lesson edit when listening to sound, in some sentences the audio seems to run according to the timing running, but no sound comes out. Subsequently, if I reduce the starting time by for example one second, the sound does play. I have heard this multiple times on different lessons both in sentence edit and in lesson edit. Apparantly a side effect of some change, hopefully not intentional.

The example I have now is in lesson “Login - LingQ” at 09:09.07 (see screenprint). Reducing the starting time to 09:08.7 and the sound runs fine.

Please correct the error.