Sound getting clipped when using io-audio driver

[s_and_m]

Hi All,

I am getting a scenario where my sound is getting clipped if I do an Alt+Tab with a Photon Application. When I checked top, I noticed that io-graphics driver was taking up a lot of CPU during those spikes.

In the release notes of QNX 6.4.0, it is mentioned that io-graphics will get higher CPU as compared to io-audio, so when io-graphics gets involved in rendering GUI, io-audio will produce a broken sound.

I tried to use the workaround that was mentioned there (increase priority of the sound driver using 'on'). This did not work.

I tried to increase max_dma_buf_size till 5 mb,but it did not work.

Please suggest me the possible way to reduce the clipping of sound or is there anything that I missed out.

[Thunderblade]

Are you sure it's a priority issue? What's the priority of the threads of io-graphics, and io-audio? Did they really change using 'on'?

What graphics driver is active? If it's the VESA driver, I think it isn't a priority issue but may be a bus saturation issue.