Yocto 2.0 Accent Trigger mutes instruments

I have problems with all accent-outputs. I allready did some measurement with the oszillosop and found following:
The ATMega1284 delivers +5V levels on MUX_A, ... INH_MUX2. Thats correct.
IC3 (4049) should make something like an inverting level converter from TTL level to +15V, but this is not working. All 6 Outputpins (A, B, C, INH1, INH2) just go from +15V (highlevel) down to +6V (low level - instead of +0V).
The following 4051 (IC114, IC111) are not able to work with this too high low level and all the intruments stay muted.

Can anybody help with this problem ? Is there a special 4049 type which works better ?

I read in other forum entrys that others have also problems with the accents and blame the 4051 for this. I think, the problem can be the 4049....

Hi there,

Use the CD4049UB from Texas instrument. It should work