I have an older HTIB made by Pioneer model HTZ 55DV. Recently I noticed it acting strangely. Namely, the Dolby/DTS advanced modes (MUSICAL, DRAMA, ACTION, VIRTUAL SURR.1, VIRTUAL SURR.2, REAR WIDE) longer are listed when I cycle through them. AUTO, STANDARD and SURROUND OFF are the only options that still work.

Secondly none of DSP modes (HALL 1, HALL 2, JAZZ, DANCE, THEATER 1, THEATER 2, SIMULATED STEREO) no longer work. The only mode it lists is DSP OFF. The DSP modes normally work with any source. The Dolby/DTS modes work with Dolby Surround, Dolby Digital or DTS encoded sources only.

I figure a part of the processing board is fried. I tried a reset but no joy.

Any tips or helpful insights before I retire my unit to another room?

Is there a surround off / effects off switch on the receiver? If so, that might be stuck "on" which would defeat the extra processing modes.

The fact that you can cycle through other settings suggests that there is a problem with an input vs a problem with the chip.

Hmm somehow I lost this thread. If it is stuck ON I have found no way of disabling it, other than pressing the DSP button (which normally cycles through the modes listed below including OFF).

The manual for that system states that the advanced and DSP modes don't work if the source is 96 kHz/24-bit. Are you by any chance using such a source? Is 96kHz lit on the front display?

I have tried CDs and DVDs all with the same result. Plus I don't think I have anything capable of 96/24. Just for kicks I am going to set the output to 48KHz to see if it is linked to the input. Nope no joy.