[FFmpeg-user] Error:Impossible to convert between the formats supported by the filter..

[tasos]

Hello.
I'm using
> ffmpeg -y  -c:v h264_cuvid -deint 1 -vsync 1 -timeout 999999 -i foo \
> -map 0:v -c:v h264_nvenc -preset slow -profile:v high -b:v 1300k 
> -pix_fmt yuv420p -map 0:a -c:a libfdk_aac \
> -ac 2 -b:a 64k -strict experimental -f mpegts foobar
and everything works fine.
When i add -hwaccel cuvid

> ffmpeg -y -hwaccel cuvid     -c:v h264_cuvid ...... the same as above
I get
> Impossible to convert between the formats supported by the filter 
> 'Parsed_null_0' and the filter 'auto_scaler_0'
> Error reinitializing filters!
> Failed to inject frame into filter network: Function not implemented
> Error while processing the decoded data for stream #0:4


This is what i get from ffprobe foo

>     Last message repeated 1 times
> Input #0, mpegts, from 'foo':
>   Duration: N/A, start: 15496.073778, bitrate: N/A
>   Program 1
>     Stream #0:0[0x1010]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, 
> stereo, s16p, 384 kb/s
>     Stream #0:1[0x1020]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, 
> stereo, s16p, 384 kb/s
>     Stream #0:2[0x1030]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, 
> stereo, s16p, 256 kb/s
>     Stream #0:3[0x1040]: Audio: mp2 ([3][0][0][0] / 0x0003), 48000 Hz, 
> stereo, s16p, 256 kb/s
>     Stream #0:4[0x200]: Video: h264 (Main) ([27][0][0][0] / 0x001B), 
> yuv420p(tv, bt709, top first), 1920x1080 [SAR 1:1 DAR 16:9], 25 fps, 
> 50 tbr, 90k tbn, 50 tbc
Any ideas please?
thanks!