Offline bounce vs. Realtime bounce significant differences

[Mano]

Today i did some offline bounces with ADC on PT 11 HDX 11.1.3
As i listened back the bounced products i was quite a bit shocked.
It sounded different than the mixes I made : Less low-end and more M than S.
So i checked my IO setup for mistaking routings...nothing wrong.
So i bounced the same mix in realtime and it sounded exactly the same as my mix. What the $!% going on here ? Because this was certainly not an ADC issue or caused by improper IO settings.( i checked this over and over again...)

Second : when i oflline-bounce several busses ( with ADC ) i noticed a latency of up to 960samples compared to the originals when importing the bounce into the session @ selection.

Session details : ProTools 11.1.3 HDX, MacPro 2014 8 core , Magma thunderbolt expressbox with 2 x HDX, 35 tracks with Waves SSLchannels bussed to 6 AUX ( with some Waves VEQ4 and Sonnox inflators)
Vocal tracks not bussed but spiced with SSLchannels followed and CLA76
Reverbs: 2CAUDIO B2 native, 2CAUDIO Aether native , Lexicon PCM native reverb Vintageplate.
Masterbus ( MAIN OUT ) McDSP ML4000 ( aax dsp) WAVES comp ( native) Kramer Tape, REDD 37, SONNOX limiter.
Automatic Delay Compensation and AVID Heat enabled.
Disk Cache @ 2 GB, playback engine 512 samples.

Both problems are reproducable in different sessions under same conditions
Can anyone shine a light on this ??